WorldWideScience
 
 
1

Equivalent widths of cool stars (Cesetti+, 2013)  

Science.gov (United States)

The near-infrared (NIR) wavelength range offers some unique spectral features, and it is less prone to the extinction than the optical one. Recently, the first flux calibrated NIR library of cool stars from the NASA Infrared Telescope Facility (IRTF) have become available, and it has not been fully exploited yet. We want to develop spectroscopic diagnostics for stellar physical parameters based on features in the wavelength range 1-5um. In this work we test the technique in the I and K bands. The study of the Y, J, H, and L bands will be presented in the following paper. An objective method for semi-empirical definition of spectral features sensitive to various physical parameters is applied to the spectra. It is based on sensitivity map - i.e., derivative of the flux in the spectra with respect to the stellar parameters at a fixed wavelength. New optimized indices are defined and their equivalent widths (EWs) are measured. (6 data files).

Cesetti, M.; Pizzella, A.; Ivanov, V. D.; Morelli, L.; Corsini, E. M.; Dalla Bonta, E.

2013-04-01

2

Pal1-I elemental equivalent widths and abundances (Monaco+, 2011)  

Science.gov (United States)

Table A1. reports the line list and atomic parameters adopted for the Palomar 1 giant Pal1-I and the Sun. For the Mn and Co lines we adopted the hyperfine structures (HFS) tabulated by Prochaska et al. (2000AJ....120.2513P). The measured equivalent width and the corresponding abundance obtained for each line are also reported. (1 data file).

Monaco, L.; Saviane, I.; Correnti, M.; Bonifacio, P.; Geisler, D.

2010-11-01

3

FUNDPAR: A program for Deriving Fundamental Parameters from Equivalent Widths  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Implementamos un programa en Fortran que determina parámetros fundamentales de estrellas de tipo solar, a partir de anchos equivalentes del Fe. La solución debe verificar tres condiciones en el método estándar: equilibrio de ionización, equilibrio de excitación e independencia entre abundancias y anchos equivalentes. Calculamos modelos de atmósfera de Kurucz con opacidades NEWODF. Detalles como el parámetro de longitud de mezcla, el sobre impulso convectivo, etc. (more) se calculan con un programa independiente. FUNDPAR calcula las incertezas por dos métodos: el criterio de Gonzalez & Vanture (1998) y utilizando la función ?² . Los resultados derivados con FUNDPAR están de acuerdo con determinaciones previas en la literatura. En particular obtuvimos parámetros fundamentales de 58 estrellas con exoplanetas. El programa está disponible en la red1. Abstract in english We implemented a Fortran code that determines fundamental parameters of solar type stars from a list of Fe line equivalent widths. The solution should verify three conditions in the standard method: ionization equilibrium, excitation equilibrium and independence between metallicity and equivalent widths. Solarscaled Kurucz model atmospheres with NEWODF opacities are calculated with an independent program. Parameter files control different details, such as the mixinglength (more) parameter and the overshooting. FUNDPAR derives the uncertainties following two methods: the criterion of Gonzalez & Vanture (1998) and the dispersion using the ?2 function. The code uses the 2009 version of the MOOG program. The results derived with FUNDPAR are in agreement with previous determinations in the literature. The program is freely available from the web1.

Saffe, C

2011-04-01

4

Tool for Automatic Measurement of Equivalent width (TAME)  

CERN Document Server

We present a tool for measuring the equivalent width (EW) in high-resolution spectra. The Tool for Automatic Measurement of Equivalent width (TAME)provides the EWs of spectral lines by profile fitting in the automatic or the interactive mode, which can yield a more precise result through the adjustment of the local continuum and fitting parameters. The automatic EW results of TAME have been verified by comparing them with the manual EW measurements by IRAF splot task using the high-resolution spectrum of the Sun, and measuring EWs in the synthetic spectra with different spectral resolutions and S/N ratios. The EWs measured by TAME agree well with manually measured values, with a dispersion of less than 2 mA. By comparing the input EWs for synthetic spectra and EWs measured by TAME, we conclude that it is reliable for measuring the EWs in a spectrum with a spectral resolution, R > 20000 and find that the errors in EWs is less than 1 mA for a S/N ratio > 100.

Kang, Wonseok

2012-01-01

5

The distribution of equivalent widths in long GRB afterglow spectra  

CERN Document Server

The extreme brightness of gamma-ray burst (GRB) afterglows and their simple spectral shape make them ideal beacons to study the interstellar medium of their host galaxies through absorption line spectroscopy. Using 69 low-resolution GRB afterglow spectra, we conduct a study of the rest-frame equivalent width (EW) distribution of features with an average rest-frame EW larger than 0.5 A. To compare an individual GRB with the sample, we develop EW diagrams as a graphical tool, and we give a catalogue with diagrams for the 69 spectra. We introduce a line strength parameter (LSP) that allows us to quantify the strength of the absorption features as compared to the sample by a single number. Using the distributions of EWs of single-species features, we derive the distribution of column densities by a curve of growth (CoG) fit. We find correlations between the LSP and the extinction of the GRB, the UV brightness of the host galaxies and the neutral hydrogen column density. However, we see no significant evolution of...

Postigo, A de Ugarte; Thoene, C C; Christensen, L; Gorosabel, J; Milvang-Jensen, B; Schulze, S; Jakobsson, P; Wiersema, K; Sanchez-Ramirez, R; Leloudas, G; Zafar, T; Malesani, D; Hjorth, J

2012-01-01

6

[O III] Equivalent Width and Orientation Effects in Quasars  

CERN Multimedia

The flux of the [OIII] line is considered to be a good indicator of the bolometric emission of quasars. The observed continuum emission from the accretion disc should instead be strongly dependent on the inclination angle theta between the disc axis and the line of sight. Based on this, the equivalent width (EW) of [OIII] should provide a direct measure of theta. Here we analyze the distribution of EW([OIII]) in a sample of ~6,000 SDSS quasars, and find that it can be accurately reproduced assuming a relatively small intrinsic scatter and a random distribution of inclination angles. This result has several implications: 1) it is a direct proof of the disc-like emission of the optical continuum of quasars; 2) the value of EW([OIII]) can be used as a proxy of the inclination, to correct the measured continuum emission and then estimate the bolometric luminosity of quasars; 3) the presence of almost edge-on discs among broad line quasars implies that the accretion disc is not aligned with the circumnuclear absor...

Risaliti, G; Marconi, A

2010-01-01

7

Observation of an H-alpha outburst in the Be star HR 4123  

Energy Technology Data Exchange (ETDEWEB)

During routine monitoring of the Be star HR 4123 during the year 1987-1988, a burst of H-alpha emission was observed on May 11, 1987. The increase was observed on May 9 and lasted until June 7, peaking to an equivalent width of 31.6 A on May 11. This short-term burst is interpreted as due to the presence of a compact object in binary motion around the Be star, which accretes the matter ejected by the Be star to give out X-rays, which in turn produce ionization in the gas to give out the H-alpha emission. The broad line at 6577.5 A observed to accompany H-alpha emission during the burst is suggested to be emission from dielectronic recombination from C III ions in a C II region around the H II region formed by the X radiation. 18 refs.

Ghosh, K.K.; Apparao, K.M.V.; Tarafdar, S.P. (Vainu Bappu Observatory, Kavalur (India); Tata Institute of Fundamental Research, Bombay (India))

1989-09-01

8

An Effective temperature calibration for solar type stars using equivalent width ratios - A fast and easy spectroscopic temperature estimation  

CERN Document Server

Aims: The precise determination of the stellar effective temperature of solar type stars is of extreme importance for Astrophysics. We present an effective temperature calibration for FGK dwarf stars using line equivalent width ratios of spectral absorption lines. Method: The ratios of spectral line equivalent width can be very sensitive to effective temperature variations for a well chosen combination of lines. We use the automatic code ARES to measure the equivalent width of several spectral lines, and use these to calibrate with the precise effective temperature derived from spectroscopy presented in a previous work. Results: We present the effective temperature calibration for 433 line equivalent width ratios built from 171 spectral lines of different chemical elements. We also make available a free code that uses this calibration and that can be used as an extension to ARES for the fast and automatic estimation of spectroscopic effective temperature of solar type stars.

Sousa, S G; Israelian, G; Santos, N C

2009-01-01

9

[Ca II triplet equivalent widths of spiral galaxy M31 and elliptical galaxy M32  

UK PubMed Central (United Kingdom)

The Calcium II triplet (Ca II T) lines in the near infrared spectral region is very important feature for late type stars, which serves as an important metallicity indicator for such stars. This is also true for stellar systems composed mainly of late type stars, such as old stellar clusters and galaxies. In this work, we made observations of the very famous spiral galaxy M31 and its dwarf elliptical companion M32, using the OMR spectrograph attached to the 2.16-meter telescope in Beijing Astronomical Observatory. Near-infrared spectra of the nuclear and disk regions on M31, as well as two slices along the major and the minor axis of M32, are derived. Equivalent widths of the Ca II triplet lines are measured using normal astrophysical spectrum analyzing techniques. The results are fundamental data for these two galaxies, which can be applied to researches for stellar population analysis of these galaxies.

Li T; Deng L; Zhao G

2000-08-01

10

Mid-IR Galaxy Classification Based on Silicate Obscuration and PAH Equivalent Width  

CERN Multimedia

We present a new diagnostic diagram for mid-infrared spectra of infrared galaxies based on the equivalent width of the 6.2 micron PAH emission feature and the strength of the 9.7 micron silicate feature. Based on the position in this diagram we classify galaxies into 9 classes ranging from continuum-dominated AGN hot dust spectra and PAH-dominated starburst spectra to absorption-dominated spectra of deeply obscured galactic nuclei. We find that galaxies are systematically distributed along two distinct branches: one of AGN and starburst-dominated spectra and one of deeply obscured nuclei and starburst-dominated spectra. The separation into two branches likely reflects a fundamental difference in the dust geometry in the two sets of sources: clumpy versus non-clumpy obscuration. Spectra of ULIRGs are found along the full length of both branches, reflecting the diverse nature of the ULIRG family.

Spoon, H W W; Houck, J R; Elitzur, M; Hao, L; Armus, L; Brandl, B R; Charmandaris, V

2006-01-01

11

DAOSPEC: An Automatic Code for Measuring Equivalent Widths in High-resolution Stellar Spectra  

Science.gov (United States)

DAOSPEC is a Fortran code for measuring equivalent widths of absorption lines in stellar spectra with minimal human involvement. It works with standard FITS format files and it is designed for use with high resolution (R>15000) and high signal-to-noise-ratio (S/N>30) spectra that have been binned on a linear wavelength scale. First, we review the analysis procedures that are usually employed in the literature. Next, we discuss the principles underlying DAOSPEC and point out similarities and differences with respect to conventional measurement techniques. Then experiments with artificial and real spectra are discussed to illustrate the capabilities and limitations of DAOSPEC, with special attention given to the issues of continuum placement; radial velocities; and the effects of strong lines and line crowding. Finally, quantitative comparisons with other codes and with results from the literature are also presented.

Stetson, P. B.; Pancino, E.

2010-11-01

12

DAOSPEC: an automatic code for measuring equivalent widths in high-resolution stellar spectra  

CERN Document Server

DAOSPEC is a Fortran code for measuring equivalent widths of absorption lines in stellar spectra with minimal human involvement. It works with standard FITS format files and it is designed for use with high resolution (R>15000) and high signal-to-noise-ratio (S/N>30) spectra that have been binned on a linear wavelength scale. First, we review the analysis procedures that are usually employed in the literature. Next, we discuss the principles underlying DAOSPEC and point out similarities and differences with respect to conventional measurement techniques. Then experiments with artificial and real spectra are discussed to illustrate the capabilities and limitations of DAOSPEC, with special attention given to the issues of continuum placement; radial velocities; and the effects of strong lines and line crowding. Finally, quantitative comparisons with other codes and with results from the literature are also presented.

Stetson, P B

2008-01-01

13

On the (Non-)enhancement of the Lya equivalent width by a multiphase interstellar medium  

DEFF Research Database (Denmark)

It has been suggested that radiative transfer effects may explain the unusually high equivalent widths (EWs) of the Lya line, observed occasionally from starburst galaxies, especially at high redshifts. If the dust is locked up inside high-density clouds dispersed in an empty intercloud medium, the Lya photons could scatter off of the surfaces of the clouds, effectively having their journey confined to the dustless medium. The continuum radiation, on the other hand, does not scatter, and would thus be subject to absorption inside the clouds. This scenario is routinely invoked when Lya EWs higher than what is expected theoretically are observed, although the ideal conditions under which the results are derived usually are not considered. Here we systematically examine the relevant physical parameters in this idealized framework, testing whether any astrophysically realistic scenarios may lead to such an effect. It is found that although clumpiness indeed facilitates the escape of Lya, it is highly unlikely that any real interstellar media should result in a preferential escape of Lya over continuum radiation. Other possible causes are discussed, and it is concluded that the observed high EWs are more likely to be caused by cooling radiation from cold accretion and/or anisotropic escape of the Lya radiation. © 2013. The American Astronomical Society. All rights reserved.

Laursen, P.; Duval, F.

2013-01-01

14

Bounded m-ary Patch-Width Are Equivalent For m > 2  

CERN Multimedia

We consider the notion of bounded m-ary patch-width and its very close relative m-constructible. We show that the notions of m-constructibility all coincide for m>2, while 1-constructibility is a weaker notion. The same holds for bounded patch-width. The cace m=2 is left open.

Shelah, S; Shelah, Saharon; Doron, Mor

2006-01-01

15

H{\\alpha} spectral monitoring of epsilon Aurig\\ae\\ 2009-2011 eclipse  

CERN Document Server

We present and analyze epsilon Aurig\\ae\\ data concerning the evolution of the H{\\alpha} line on the occasion of the 2009 International observation campaign launched to cover the eclipse of this object. We visually inspect the dynamical spectrum constructed from the data and analyze the evolution with time of the EW (Equivalent Width) and of the radial velocity. The spectroscopic data reveal many details which confirm the complexity of the Aurig\\ae\\ system. The object is far from being understood. In particular, according to our measurements, the eclipse duration has been underestimated. A complete analysis of details revealed by our data would require much time and effort. Observers are encouraged to continue monitoring the H{\\alpha} line out of eclipse in the hope that it will provide further important information.

Mauclaire, B; Garrel, T; Leadbeater, R; Lopez, A

2012-01-01

16

H-alpha monitoring of OJ 287 in 2005-08  

CERN Document Server

We present the results of H-alpha monitoring of the BL Lac object OJ 287 with the VLT during seven epochs in 2005-08. We were able to detect five previously undetected narrow emission lines, 6548,6583[NII], 6563H-alpha$ and 6716,6731[SII] during at least one of the epochs and a broad H-alpha feature during two epochs. The broad H-alpha luminosity was a factor ~10 lower in 2005-08 than in 1984 when the line was previously detected and a factor ~10 lower than what is observed in quasars and Seyfert galaxies at the same redshift. The data are consistent with no change in the position or luminosity of the H-alpha line in 2005-08. The width of the H-alpha line was 4200 +- 500 km/s, consistent with the width in 1984.

Nilsson, K; Lehto, H J; Sillanpää, A

2010-01-01

17

High-redshift Ly alpha emitters with a large equivalent width: Properties of i-dropout galaxies with an NB921-band depression in the Subaru Deep Field  

CERN Document Server

We report new follow-up spectroscopy of i-dropout galaxies with an NB921-band depression found in the Subaru Deep Field. The NB921-depressed i-dropout selection method is expected to select galaxies with large equivalent width Ly alpha emission over a wide redshift range, 6.0equivalent widths are 153A and 114A, which are lower limits on the intrinsic equivalent widths. Through our spectroscopic observations (including previous ones) of NB921-depressed i-dropout galaxies, we identified 5 galaxies in total with a rest-frame equivalent width larger than 100A at 6.0equivalent width, in a wider redshift range than usual narrow-band excess techniques. B...

Nagao, T; Maiolino, R; Marconi, A; Kashikawa, N; Ajiki, M; Hattori, T; Ly, C; Malkan, M A; Motohara, K; Ohta, K; Sasaki, S S; Shioya, Y; Taniguchi, Y; Nagao, Tohru; Murayama, Takashi; Maiolino, Roberto; Marconi, Alessandro; Kashikawa, Nobunari; Ajiki, Masaru; Hattori, Takashi; Ly, Chun; Malkan, Matthew A.; Motohara, Kentaro; Ohta, Kouji; Sasaki, Shunji S.; Shioya, Yasuhiro; Taniguchi, Yoshiaki

2007-01-01

18

X-Ray Reflection Nebulae with Large Equivalent Widths of Neutral Iron Ka Line in the Sgr C Region  

CERN Document Server

This paper reports on the first results of the Suzaku observation in the Sgr C region. We detected four diffuse clumps with strong line emission at 6.4keV, Ka from neutral or low-ionized Fe. One of them, M359.38-0.00, is newly discovered with Suzaku. The X-ray spectra of the two bright clumps, M359.43-0.07 and M359.47-0.15, after subtracting the Galactic center diffuse X-ray emission (GCDX), exhibit strong Ka line from FeI with large equivalent widths (EWs) of 2.0-2.2keV and clear Kb of FeI. The GCDX in the Sgr C region is composed of the 6.4keV- and 6.7keV-associated components. These are phenomenologically decomposed by taking relations between EWs of the 6.4keV and 6.7keV lines. Then the former EWs against the associated continuum in the bright clump regions are estimated to be 2.4(+2.3_-0.7)keV. Since the two different approaches give similar large EWs of 2keV, we strongly suggest that the 6.4keV clumps in the Sgr C region are due to X-ray reflection/fluorescence (the X-ray reflection nebulae).

Nakajima, Hiroshi; Nobukawa, Masayoshi; Matsumoto, Hironori; Koyama, Katsuji; Murakami, Hiroshi; Senda, Atsushi; Yamauchi, Shigeo

2008-01-01

19

Halpha Equivalent Widths from the 3D-HST survey: evolution with redshift and dependence on stellar mass  

CERN Multimedia

We investigate the evolution of the Halpha equivalent width, EW(Halpha), with redshift and its dependence on stellar mass, taking advantage of the first data from the 3D-HST survey, a large spectroscopic Treasury program with the Hubble Space Telescope WFC3. Combining our Halpha measurements of 854 galaxies at 0.8

Fumagalli, Mattia; Franx, Marijn; Brammer, Gabriel; van Dokkum, Pieter; da Cunha, Elisabete; Kriek, Mariska; Lundgren, Britt; Momcheva, Ivelina; Rix, Hans-Walter; Schmidt, Kasper B; Skelton, Rosalind E; Whitaker, Katherine E; Labbe, Ivo; Nelson, Erica

2012-01-01

20

The H alpha Galaxy Survey. VIII. Close companions and interactions, and the definition of starbursts  

CERN Multimedia

(Shortened) We consider the massive star formation properties, radial profiles, and atomic gas masses of those galaxies in our H alpha Galaxy Survey, a representative sample of the local Universe of 327 disk galaxies, that have close companion galaxies, in comparison with a matched control sample of galaxies without companions. We find that the presence of a close companion raises the star formation rate by a factor of just under two, while increasing hardly at all the equivalent width of the H alpha emission. This means that although statistically galaxies with close companions form stars at a higher rate, they do this over extended periods of time, and not as bursts. We find no significant increase in the central concentration of the star formation as a result of the presence of a close companion. The fraction of truly interacting or merging galaxies is very small in the local Universe, at around 2%, and possibly 4% of bright galaxies. Most of these interacting galaxies currently have unremarkable star form...

Knapen, Johan H

2009-01-01

 
 
 
 
21

Comparison of the Halpha equivalent width of HII regions in a flocculent and a grand design galaxy: possible evidences for IMF variations  

CERN Document Server

We present here a study of the Halpha equivalent widths of the flocculent galaxy NGC 4395 and the grand design galaxy NGC 5457. A difference between the mean values of the Halpha equivalent widths for the two galaxies has been found. Several hypotheses are presented in order to explain this difference: differences in age, metallicity, star formation rate, photon leakage and initial mass function. Various tests and Monte Carlo models are used to find out the most probable cause of this difference. The resultsshow that the possible cause for the difference could be a variation in the initial mass function. This difference is such that it seems to favor a fraction of more massive stars in the grand design galaxy when compared with the flocculent galaxy. This could be due to a change of the environmental conditions due to a density wave.

Cedres, B; Tomita, A; Cedres, Bernabe; Cepa, Jordi; Tomita, Akihiko

2005-01-01

22

DEFPOS H${\\alpha}$ Observations of W80 Complex  

CERN Document Server

We present H${\\alpha}$ emission line measurements of the W80 nebular complex. A total of 26 regions have been observed inside the nebula with the Dual Etalon Fabry-Perot Optical Spectrometer (DEFPOS) system at the f/48 Coude focus of 150 cm RTT150 telescope located at TUBITAK National Observatory (TUG) in Antalya/Turkey. The intensities, the local standard of rest (LSR) velocities ($V_{LSR}$), heliocentric radial velocities ($V_{HEL}$) and the linewidths at Full Width at Half Maximum (FWHM) of the H${\\alpha}$ emission lines have been determined from these observations. They lie in the range of 259 to 1159 Rayleigh {1R = 10$^{6}/4\\pi$ photons cm$^{-2}$ sr$^{-1}$ s$^{-1}$ = 2.4110$^{-7}$ erg cm$^{-2}$ sr$^{-1}$ s$^{-1}$ at H${\\alpha}$.} (R), 4 to 12 km s$^{-1}$ and 44 to 55 km s$^{-1}$, respectively. The radial velocity measurements show that there are several maxima and minima inside the W80. The new results confirm the literature that complex seems to be rather a uniform in radial velocity and no seen turbule...

Aksaker, Naz\\im

2012-01-01

23

On the effect of common envelope on radial velocity curves and on equivalent widths of absorption lines in close binaries  

International Nuclear Information System (INIS)

Variations of equivalen widths of absorption lines and of the radial velocities with the phase of the orbital period have been calculated for stars in a binary system with an account of the absorption component originating in a common spherically symmetric envelope having the radial opacity gradient. It is shown that a general expansion or contraction of the envelope may give rise to the distortion of the sinusoidal shape of radial velocity curves which is conventionally interpreted in terms of gas streams or is ascribed to the effect of elliptical orbit.

1985-01-01

24

First results of an H-alpha based search of classical Be stars in the Perseus Arm and beyond  

CERN Multimedia

We investigate a region of the Galactic plane, between 120 <= l <= 140 and -1 <= b <= +4, and uncover a population of moderately reddened (E(B-V) \\sim 1) classical Be stars within and beyond the Perseus and Outer Arms. 370 candidate emission line stars (13 <= r <= 16) selected from the INT Photometric H-alpha Survey of the Northern Galactic plane (IPHAS) have been followed up spectroscopically. A subset of these, 67 stars with properties consistent with those of classical Be stars, have been observed at sufficient spectral resolution (Delta_lambda \\sim 2 - 4 Angstrom) at blue wavelengths to narrow down their spectral types. We determine these to a precision estimated to be +/- 1 sub-type and then we measure reddenings via SED fitting with reference to appropriate model atmospheres. Corrections for contribution to colour excess from circumstellar discs are made using an established scaling to H-alpha emission equivalent width. Spectroscopic parallaxes are obtained after luminosity class has b...

Raddi, R; Fabregat, J; Steeghs, D; Wright, N J; Sale, S E; Farnhill, H J; Barlow, M J; Greimel, R; Sabin, L; Corradi, R M L; Drake, J J

2013-01-01

25

H$\\alpha$ kinematics of KPG 390  

CERN Multimedia

In this work we present scanning Fabry-Perot H$\\alpha$ observations of the isolated interacting galaxy pair NGC 5278/79 obtained with the PUMA Fabry-Perot interferometer. We derived velocity fields, various kinematic parameters and rotation curves for both galaxies. Our kinematical results together with the fact that dust lanes have been detected in both galaxies, as well as the analysis of surface brightness profiles along the minor axis, allowed us to determine that both components of the interacting pair are trailing spirals.

Repetto, P; Fuentes-Carrera, R Gabbasov I

2009-01-01

26

Discovery of a very cool object with extraordinarily strong H(alpha) emission  

CERN Document Server

We report on the finding of the strongest H(alpha) emission -pseudoequivalent width of 705 Angstrom- known so far in a young, late type dwarf. This object, named as SOri71, is a substellar candidate member of the 1-8 Myr star cluster sigma Orionis. Due to its overluminous location in color-magnitude diagrams, SOri71 might be younger than other cluster members, or a binary of similar components. Its mass is in the range 0.021-0.012 M(sun), depending on evolutionary models and possible binarity. The broad H(alpha) line of SOri71 appears asymmetric, indicative of high velocity mass motions in the H(alpha) forming region. The origin of this emission is unclear at the present time. We discuss three possible scenarios: accretion from a disk, mass exchange between the components of a binary system, and emission from a chromosphere.

Barrado y Navascués, D; Martín, E L; Béjar, V J S; Rebolo, R; Mundt, R; Navascues, David Barrado y; Osorio, Maria Rosa Zapatero; Martin, Eduardo L.; Bejar, Victor J.S.; Rebolo, Rafael; Mundt, Reinhard

2002-01-01

27

Study of a Complete Sample of H-alpha Emission-Line Galaxies  

Science.gov (United States)

The Universidad Complutense de Madrid survey is a long project with the aim of finding and analyzing star formation galaxies using the H-alpha line as the tracer for the massive star formation processes. In order to obtain a representative complete sample of such a technique, several objective prism plates were taken with the Schmidt telescope at Calar Alto Almeria (Spain). The combination of IIIaF Kodak emulsion and a RG630 filter was used for covering the red spectral region, from 6400A to a redshift of 0.045 for the H-alpha line. A compilation of descriptions and positions is presented for 272 emission-line candidates from 545 square degrees of the sky. Also apparent magnitude and equivalent width estimators are given. Spectroscopical observations were carried out for the full sample of H-alpha emission--line galaxy (ELGs) candidates. All the spectroscopic information is presented in the form of an appendix. Each ELG was classified into one of eight natural groups of star forming galaxies. The ELG types most commonly found (47%) are intermediate to low-luminosity objects with a very intense star-formation region which dominates the optical output of the galaxy. This kind of ELGs is similar to the galaxy population detected in the blue objective prism surveys, but what is more important, it was found a second population (43%) of star-forming galaxies with low ionization or high extinction properties. This ELGs group are not detected nor in the blue (University of Michigan survey) neither in other surveys (Kiso, IRAS, Markarian) using other selection techniques. Emission-line ratio diagnostic diagrams reveal that the ELGs in the different natural groups tend to have distinctly different line ratios. This suggests that the various ELGs types differ from one another in terms of metal abundance of their ionized gas, the ionization parameter and the relative importance of the starburst process in the galaxy, confirming a previous similar result found for the UM survey. There is present a trend for lower metallicities at lower luminosities. It has not been found any galaxy with metallicity lower than I Zw 18. >From the original IRAS data it was obtained for the whole sample the far-infrared fluxes. In the one hand it is necessary to apply a two-component model for reproducing the general behaviour of the UCM sample at that spectral range. In the other hand the FIR properties of a H-alpha selected sample are well differentiated against FIR-selected samples. The line+continuum flux is the main selection parameter for the UCM survey, but other secondary effects are discussed. An study of the luminosity and spatial distribution of the UCM galaxies is presented. The ELGs follow at great scale the distribution of the catalog galaxies. Using the UCM ELGs as SFR tracers a luminosity function for the SFR at the local Universe is computed. These result has important implications for our understanding of the origin of the star formation phenomena as well as the evolution of the galaxies. In the future, we propose to extend the survey to new sky regions and deeper redshifts and to quantify the SFR at the Local Universe by means of the UCM sample. The original is written in spanish. (SECTION: Dissertation Summary)

Gallego Maestro, Jesus

1995-07-01

28

Flux calibration of the AAO/UKST SuperCOSMOS H-alpha Survey  

CERN Document Server

The AAO/UKST SuperCOSMOS H-alpha Survey (SHS) of the southern Galactic plane was, when completed in 2003, a powerful new addition to wide-field surveys. It has a combination of areal coverage, spatial resolution and flux sensitivity in a narrow imaging band which still marks it out today as an excellent resource for the astronomical community. The 233 separate fields are available online in digital form, with each field covering 25 square degrees. The SHS has been the motivation for equivalent surveys in the north, and new digital H-alpha surveys now beginning in the south such as VPHAS+. The SHS has been the foundation of many important follow-up discovery projects in the southern sky with the Macquarie/AAO/Strasbourg H-alpha (MASH) planetary nebula project being a particularly successful example. However, the full astrophysical potential of the SHS has been hampered by lack of a clear route to acceptable flux calibration from the base photographic data. We have determined the calibration factors for 170 sep...

Frew, David J; Parker, Quentin A; Pierce, Mark J; Gunawardhana, M L P; Reid, W A

2013-01-01

29

Study of H-alpha emission from solar limb prominences using Fabry-Perot interferometry  

Energy Technology Data Exchange (ETDEWEB)

The Fabry-Perot interferometer is an effective dispersing element for studying H-alpha emission from solar limb prominences. Having a reflecting coefficient in the range 0.85-0.95, the Fabry-Perot multiple beam interferometer behaves as an angular filter, forming circular interference fringes. Results from an investigation performed at the solar installation at Boyden Observatory in South Africa are presented, where a photographic Fabry-Perot interferometer was used to obtain fringes from the 656.3-nm H-alpha emission during April and May 1980. Successful scans were made with air admitted to the interferometer pressure chamber, and reduction of the data on photon count and chamber pressure was made by a UNIVAC 1108 computer. Sketches and profiles from the limb prominences are shown a table of fringe half-widths, corrected for the instrumental width of the interferometer, were obtained by matching a Voigt function by a least-squares computer fit to the observed scanned Fabry-Perot fringe profiles.

Jarrett, A.H. (Boyden Observatory, Bloemfontein, Republic of South Africa); Stapelberg, J. (Orange Free State, University, Bloemfontein, Republic of South Africa)

1981-02-01

30

Filament and Flare Detection in H{\\alpha} image sequences  

CERN Multimedia

Solar storms can have a major impact on the infrastructure of the earth. Some of the causing events are observable from ground in the H{\\alpha} spectral line. In this paper we propose a new method for the simultaneous detection of flares and filaments in H{\\alpha} image sequences. Therefore we perform several preprocessing steps to enhance and normalize the images. Based on the intensity values we segment the image by a variational approach. In a final postprecessing step we derive essential properties to classify the events and further demonstrate the performance by comparing our obtained results to the data annotated by an expert. The information produced by our method can be used for near real-time alerts and the statistical analysis of existing data by solar physicists.

Riegler, Gernot; Pötzi, Werner; Veronig, Astrid

2013-01-01

31

The MSSSO wide field CCD H-alpha imaging survey  

Science.gov (United States)

A wide-field H-alpha survey of the Galactic Plane has been initiated by Mount Stromlo & Siding Spring Observatories in collaboration with the University of Sydney. The primary aim of the survey is to obtain images of the Galactic Plane in H-alpha and red continuum filters which will be compared with radio continuum images at 843 MHz from the Molonglo Observatory Synthesis Telescope (MOST). The secondary aim is to obtain images in [OIII] and [SII] to provide additional information on the nature of excitation in HII regions. Thirdly, additional images will be taken in B, V and I of interesting areas suitable for general publications as coloured reproductions. The images are taken with a 400 mm f/4.5 Nikkor-Q lens in conjunction with a 2K x 2K SITe thinned CCD. The resolution is 12'' per pixel and the pixel size is 24 microns giving a 7 x 7 sq. deg. field of view. H-alpha and red continuum observations are expected to be completed by the end of 1997. It is planned to make the results from the survey available on CD ROM and possibly video.

Buxton, M.; Bessell, M.; Watson, B.

1998-04-01

32

The H alpha Galaxy Survey. III. Constraints on supernova progenitors from spatial correlations with H alpha emission  

CERN Multimedia

Aims: We attempt to constrain progenitors of the different types of supernovae from their spatial distributions relative to star formation regions in their host galaxies, as traced by H alpha + NII line emission. Methods: We analyse 63 supernovae which have occurred within galaxies from our H alpha survey of the local Universe. Three statistical tests are used, based on pixel statistics, H alpha radial growth curves, and total galaxy emission-line fluxes. Results: Many more type II supernovae come from regions of low or zero emission line flux than would be expected if the latter accurately traces high-mass star formation. We interpret this excess as a 40% `Runaway' fraction in the progenitor stars. Supernovae of types Ib and Ic do appear to trace star formation activity, with a much higher fraction coming from the centres of bright star formation regions than is the case for the type II supernovae. Type Ia supernovae overall show a weak correlation with locations of current star formation, but there is evide...

James, P A

2006-01-01

33

Automatic Selection of H-alpha Emission-Line Galaxies  

Science.gov (United States)

We have developed a procedure for the automatic selection of emission-line galaxies candidates from the digitization of objective prism plates. This procedure has been applied over two pair of direct and prism plates of the Universidad Complutense de Madrid (UCM) survey, digitized by the fast and high performance microdensitometer MAMA (Machine Automatique a Mesurer pour l'Astronomie) located at the Observatoire de Paris. The plates where obtained with the Schmidt Telescope at Calar Alto Observatory in Almeria (Spain). The instrumental setup used for the acquisition of the prism plates (IIIa-F emulsion and RG630 filter) allows to register the H-alpha +[NII] emission for galaxies up to z <= 0.045. Therefore the criteria developed for the automatic selection of ELGs candidates consist in identifying the H-alpha emission feature in the extracted monodimensional prism spectra. We have noted that there is not a nitid edge to distinguish between the spectra showing the H-alpha line in emission and the rest. Consequently we have studied the residual obtained after the estimation of the continuum and the variation of the slopes calculated over each spectrum in order to identify the line feature. The efficiency of this technique has been tested by comparing the results obtained applying the automatic procedure with those achieved after a careful visual search for the candidates, as performed up to date in the UCM and similar surveys. The results show us that the automatic procedure only ignore very extended and near saturated known galaxies with well resolved emitting regions located at the external regions. Spectroscopic observations of moderate dispersion for the whole set of candidates selected both automatic and visually show that the former has been able, not only to select the 100% of candidates with confirmed emission recognized also by visual means, but also, and what is more important, to identify a 29% more of confirmed ELGs, without lost of efficiency by the increase of spurious identifications. The digitization of the plates has allowed us to measure a set of accurate observational parameters as positions, magnitudes, sizes and redshifts that will permit to perform statistical analysis of this kind of objects before carrying out specific observations with larger telescopes. Since our plates have not sensitometric spots to calculate its characteristic curve, it has been necessary to obtain external calibrations by comparing with calibrated data offered by several catalogs. We have tested that the precision achieved using this method is mainly limited by the accuracy of the different catalog employed. The redshift of the candidates can be derived from the location of the H-alpha line on the prism spectra. Since they have no spectral features to refer the position of the H$\\alpha$ line, the positions of the objects in the direct plate and their transformations to the prism one have been used to provide a reference point which is dependent neither on magnitude, nor on color, nor spatial light distribution. A precision of 0.003 is reached when measuring redshifts by this method. Finally, the comparison of the candidate samples obtained from two plates of our survey covering the same area on the sky allows the study of the selection effects that affects the identification of the H-alpha line in photographic prism plates. The parameter EW X F of the emission H-alpha +[NII] can be used as a threshold that inform us about the unambiguous identification of the emission in the prism spectra, being 10^-13 erg s^-1 cm^-2A the mean value of this parameter for the whole sample of the UCM survey. We have also developed an algorithm to simulate the expected objective-prism spectra for an object by using different instrumental setups. The simulation permits to investigate the different combinations of EW, fluxes and magnitude that allow the detection of the H$\\alpha$ line in the plates and will be used in the near future to predict the expected spectra by the substitution of the photographic emulsion with CCD detectors. (SECTION: D

Lasheras, Oscar Alonso

1996-06-01

34

The synthesis of 4-[sup 2]H-[alpha]-farnesene and 1-[sup 2]H-[alpha]-farnesene  

Energy Technology Data Exchange (ETDEWEB)

[alpha]-Farnesene deuterated at C1 or C4 was synthesised by regiospecific deuteration of 2-geranyl-3-methylsulpholene (2). Treatment of (2) with butyl lithium in dimethylpropenylurea (DMPU) mediated THF resulted in deprotonation at C2. Quenching with D[sub 2]O/CH[sub 3]CO[sub 2]D gave a mixture of deuterated sulpholenes (43-68%). Thermal elimination of sulphur dioxide gave 4-[sup 2]H-[alpha]-farnesene (85%) but with low deuterium incorporation (60%) and poor regiospecificity. Treatment of (2) with butyl lithium in TMEDA mediated THF resulted in deprotonation at C5 with minimal bond migration (1%). Quenching with D[sub 2]O/CH[sub 3]CO[sub 2]D yielded 5-[sup 2]H-2-geranyl-3-methylsulpholene (75%) which on thermolysis gave 1-[sup 2]H-[alpha]-farnesene (86%) with high regiospecificity and improved deuteration (85%). Some mechanistic aspects of the alkylation of 3-methylsulpholenes are discussed. (Author).

Fielder, S.; Rowan, D.D.; Reay, P.F. (Horticulture and Food Research Inst. of New Zealand Ltd., Palmerston North (New Zealand))

1993-10-01

35

The interacting galaxy pair KPG 390: H$\\alpha$ kinematics  

CERN Multimedia

In this work we present scanning Fabry-Perot H$\\alpha$ observations of the isolated interacting galaxy pair NGC 5278/79 obtained with the PUMA Fabry-Perot interferometer. We derived velocity fields and rotation curves for both galaxies. For NGC 5278 we also obtained the residual velocity map to investigate the non-circular motions, and estimated its mass by fitting the rotation curve with a disk+halo components. We test three different types of halo (pseudo-isothermal, Hernquist and Navarro Frenk White) and obtain satisfactory fits to the rotation curve for all profiles. The amount of dark matter required by pseudo-isothermal profile is about ten times smaller than, that for the other two halo distributions. Finally, our kinematical results together with the analysis of dust lanes distribution and of surface brightness profiles along the minor axis allowed us to determine univocally that both components of the interacting pair are trailing spirals.

Repetto, P; Gabbasov, R; Fuentes-Carrera, I

2010-01-01

36

Uncovering the Outflow Driven by the Brown Dwarf LS-RCr A1: H-alpha as a Tracer of Outflow Activity in Brown Dwarfs  

CERN Multimedia

It is now apparent that classical T Tauri-like outflows commonly accompany the formation of young brown dwarfs. To date two optical outflows have been discovered and results presented in this paper increase this number to three. Using spectro-astrometry the origin of the LS-RCrA 1 forbidden emission lines in a blue-shifted outflow is confirmed. The non-detection of the red-shifted component of the outflow in forbidden lines, along with evidence for some separation between low and high velocity outflow components, do not support the hypothesis that LS-RCrA 1 has an edge-on accretion disk. The key result of this analysis is the discovery of an outflow component to the H-alpha line. The H-alpha line profile has blue and red-shifted features in the wings which spectro-astrometry reveals to also originate in the outflow. The discovery that H-alpha emission in BDs can have a significant contribution from an outflow suggests the use of H-alpha line widths as a proxy of mass accretion in BDs is not clear-cut. This me...

Whelan, E T; Bacciotti, F

2009-01-01

37

Association of type II solar radio bursts with coronal structures above H-alpha filament channels  

Energy Technology Data Exchange (ETDEWEB)

A study of type II solar radio bursts recorded at 160 MHz by the Culgoora radioheliograph during 1980 to 1982 shows that the radio emission occurs above H-alpha filaments rather than above H-alpha flares. This suggests that the type II radio emission most probably originates from within a coronal helmet streamer overlying the filament channel. 9 references.

Stewart, R.T.

1984-09-01

38

The H-alpha Luminosity Function and Star-Formation Rate Volume Density at z=0.8 from the NEWFIRM H-alpha Survey  

CERN Multimedia

[Abridged] We present new measurements of the H-alpha luminosity function (LF) and SFR volume density for galaxies at z~0.8. Our analysis is based on 1.18$\\mu$m narrowband data from the NEWFIRM H-alpha Survey, a comprehensive program designed to capture deep samples of intermediate redshift emission-line galaxies using narrowband imaging in the near-infrared. The combination of depth ($\\approx1.9\\times10^{-17}$ erg s$^{-1}$ cm$^{-2}$ in H-alpha at 3$\\sigma$) and areal coverage (0.82 deg$^2$) complements other recent H-alpha studies at similar redshifts, and enables us to minimize the impact of cosmic variance and place robust constraints on the shape of the LF. The present sample contains 818 NB118 excess objects, 394 of which are selected as H-alpha emitters. Optical spectroscopy has been obtained for 62% of the NB118 excess objects. Empirical optical broadband color classification is used to sort the remainder of the sample. A comparison of the LFs constructed for the four individual fields reveals signific...

Ly, Chun; Dale, Daniel A; Momcheva, Ivelina; Salim, Samir; Staudaher, Shawn; Moore, Carolynn A; Finn, Rose

2010-01-01

39

Structure and star formation in disk galaxies III. Nuclear and circumnuclear H alpha emission  

CERN Document Server

From H alpha images of a carefully selected sample of 57 relatively large, Northern spiral galaxies with low inclination, we study the distribution of the H alpha emission in the circumnuclear and nuclear regions. At a resolution of around 100 parsec, we find that the nuclear H alpha emission in the sample galaxies is often peaked, and significantly more often so among AGN host galaxies. The circumnuclear H alpha emission, within a radius of two kpc, is often patchy in late-type, and absent or in the form of a nuclear ring in early-type galaxies. There is no clear correlation of nuclear or circumnuclear H alpha morphology with the presence or absence of a bar in the host galaxy, except for the nuclear rings which occur in barred hosts. The presence or absence of close bright companion galaxies does not affect the circumnuclear H alpha morphology, but their presence does correlate with a higher fraction of nuclear H alpha peaks. Nuclear rings occur in at least 21% (+-5%) of spiral galaxies, and occur predomina...

Knapen, J H

2004-01-01

40

The clustering and evolution of H-alpha emitters at z~1 from HiZELS  

CERN Document Server

The clustering properties of a well-defined sample of 734 H-alpha emitters at z=0.84 obtained as part of the Hi-z Emission Line Survey (HiZELS) are investigated. The spatial correlation function is very well-described by (r/r_0)^-1.8, with r_0=2.7+-0.3Mpc/h. The correlation length r_0 increases strongly with H-alpha luminosity, L_H-alpha, from r_0~2Mpc/h for the most quiescent galaxies (star-formation rates of ~4M_sun/yr), up to r_0>5Mpc/h for the brightest galaxies in H-alpha. The correlation length also increases with increasing rest-frame K-band luminosity (M_K), but the r_0-L_H-alpha correlation maintains its full statistical significance at fixed M_K. At z=0.84, star-forming galaxies classified as irregulars or mergers are much more clustered than discs and non-mergers, but once the samples are matched in L_H-alpha and M_K, the differences vanish, implying that the clustering is independent of morphological type at z~1. The typical H-alpha emitters found at z=0.84 reside in dark-matter haloes of ~10^12M_...

Sobral, David; Geach, James E; Smail, Ian; Cirasuolo, Michele; Garn, Timothy; Dalton, Gavin B; Kurk, Jaron

2009-01-01

 
 
 
 
41

Observatons of NGC 3077 Galaxy in Narrow Band [SII] and H_alpha Filters  

CERN Multimedia

We present observations of the HI tidal arm near dwarf galaxy NGC 3077 (member of the M81 galaxy group) in narrow band [SII] and H_alpha filters. Observations were carried out in March 2011 with the 2m RCC telescope at NAO Rozhen, Bulgaria. Our search for possible supernova remnant candidates (identified as sources with enhanced [SII] emission relative to their H_alpha emission) in this region yielded no sources of this kind. Nevertheless, we found a number of objects with significant H_alpha emission that probably represent uncatalogued, low brightness HII regions.

Andjelic, M; Arbutina, B; Ilic, D; Urosevic, D

2011-01-01

42

Correlations between MIR, FIR, H$\\alpha$, and FUV Luminosities for SWIRE galaxies  

CERN Document Server

e present and analyze the correlations between mid-infrared (MIR), far-infrared (FIR), total-infrared (TIR), H$\\alpha$, and FUV luminosities for star-forming galaxies, composite galaxies and AGNs, based on a large sample of galaxies selected from the $Spitzer$ SWIRE fields. The MIR luminosities of star-forming galaxies are well correlated with their H$\\alpha$, TIR and FUV luminosities, and we re-scaled the MIR-derived SFR formulae according to the above correlations with differences less than 15%. We confirm the recent result by calzetti et al. (2007) that the combined observed H$\\alpha$ + 24$\\mu$m luminosities L(H$\\alpha IR and TIR luminosities are completely following those of star-forming galaxies.

Zhu, Yi-Nan; Cao, Chen; Li, Hai-Ning

2008-01-01

43

On the Sensitivity of the H$\\alpha$ Scattering Polarization to Chromospheric Magnetism  

CERN Multimedia

A particularly interesting line for exploring the physical conditions of the quiet solar chromosphere is H$\\alpha$, but its intensity profile is magnetically insensitive and the small circular polarization signatures produced by the longitudinal Zeeman effect come mainly from the underlying photosphere. Here we show that the Hanle effect in H$\\alpha$ provides quantitative information on the magnetism of the quiet chromosphere. To this end, we calculate the response function of the emergent scattering polarization to perturbations in the magnetic field.

Stepan, Jiri

2010-01-01

44

H-alpha variability of the recurrent nova T Coronae Borealis  

CERN Multimedia

We analyze H-alpha observations of the recurrent nova T CrB obtained during the last decade. For the first time the H-alpha emission profile is analyzed after subtraction of the red giant contribution. Based on our new radial velocity measurements of the H-alpha emission line we estimate the component masses of T CrB. It is found that the hot component is most likely a massive white dwarf. We estimate the inclination and the component masses to be i~67 deg, Mwd = 1.37 +/-0.13 Msun and Msec=1.12 +/-0.23 Msun, respectively. The radial velocity of the central dip in the H-alpha profile changes nearly in phase with that of the red giant's absorption lines. This suggests that the dip is most likely produced by absorption in the giant's wind. Our observations cover an interval when the H-alpha and the U-band flux vary by a factor of ~6, while the variability in B and V is much smaller. Based on our observations, and archival ultraviolet and optical data we show that the optical, ultraviolet and H-alpha fluxes stron...

Stanishev, V; Tomov, N; Marziani, P

2003-01-01

45

H-alpha +[NII] Observations of the HII Regions in M81  

CERN Document Server

In a first of a series of studies of the H-alpha + [NII] emission from nearby spiral galaxies, we present measurements of H-alpha + [NII] emission from HII regions in M81. Our method uses large-field-CCD images and long-slit spectra, and is part of the ongoing Beijing-Arizona-Taipei-Connecticut Sky Survey. The CCD images are taken with the NAOC 0.6/0.9m f/3 Schmidt telescope at the Xinglong Observing Station, using a multicolor filter set. Spectra of 10 of the brightest HII regions are obtained using the NAOC 2.16m telescope with a Tek 1024 X 1024 CCD. The continua of the spectra are calibrated by flux-calibrated images taken from the Schmidt observations. We determine the continuum component of our H-alpha + [NII] image via interpolation from the more accurately-measured backgrounds (M81 starlight) obtained from the two neighboring (in wavelength) BATC filter images. We use the calibrated fluxes of H-alpha + [NII] emission from the spectra to normalize this interpolated, continuum-subtracted H-alpha + [NII] ...

Lin, W P; Burstein, D; Windhorst, R A; Chen, J S

2003-01-01

46

H-$\\alpha$ Imaging of Early-type(Sa-Sab) Spiral Galaxies, 1  

CERN Document Server

H-alpha and continuum images are presented for 27 nearby early-type(Sa-Sab) spiral galaxies. Contrary to popular perception, the images reveal copious massive star formation in some of these galaxies. A determination of the H-alpha morphology and a measure of the H-alpha luminosity suggests that early-type spirals can be classified into two broad categories based on the luminosity of largest HII region in the disk. The first category includes galaxies for which the individual HII regions have L(H-alpha) 10^(39) erg/s. All category 2 galaxies show either prominent dust lanes or other morphological peculiarities such as tidal tails which suggests that the anomalously luminous HII regions in category 2 galaxies may have formed as a result of a recent interaction. The observations, which are part of an on-going H-alpha survey, reveal early-type spirals to be a heterogeneous class of galaxies that are evolving in the current epoch. We have also identified some systematic differences between the classifications of...

Hameed, S A; Hameed, Salman; Devereux, Nick

1999-01-01

47

A Model for the Scattered Light Contribution and Polarization of the Diffuse $H\\alpha$ Galactic Background  

CERN Multimedia

We present Monte Carlo simulations of the Diffuse H$\\alpha$ Galactic Background. Our models comprise direct and multiply scattered H$\\alpha$ radiation from the kpc scaleheight Warm Ionized Medium and midplane H II regions. The scattering is off dust that is assumed to be well mixed with the gas, with an axisymmetric density distribution taken from the literature. The results of our simulations are all-sky H$\\alpha$ images that enable us to separate out the contributions of direct and scattered radiation. We also determine how far the model H$\\alpha$ photons have traveled, i.e., how far we see into the Galaxy at H$\\alpha$. Our models reproduce the overall characteristics of the observed H$\\alpha$ background and predict the scattered H$\\alpha$ intensity at high latitudes is in the range 5% to 20% of the total intensity, in agreement with estimations based on [S II]/H$\\alpha$ and [O III]/H$\\alpha$ line ratio measurements. The polarization arising from dust scattering of H$\\alpha$ from midplane H II regions is pr...

Wood, K; Wood, Kenneth; Reynolds, Ron

1999-01-01

48

Probable detection of H-alpha emission from a very high velocity cloud in Cetus  

International Nuclear Information System (INIS)

A high-sensitivity search for H-alpha emission from a -300 km/s H-I cloud in Cetus was performed using a large-aperture Fabry-Perot spectrometer. Weak emission features were noted in the H-alpha spectra at radial velocities coinciding with the 21-cm emission. The H-alpha surface brightness of the cloud is found to be 2.0 + or - 0.5 x 10 to the -8th ergs/sq cm per s per sr. The results are used to set an upper limit of 200,000/sq cm per s on the flux of Lyman-continuum photons in the vicinity of the cloud, almost a factor of 10 lower than the flux estimated to be present within the Galactic halo and comparable to some estimates for the intergalactic EUV radiation field. 17 refs.

1989-01-01

49

Isobaric multiplet width equation.  

Science.gov (United States)

The isobaric multiplet width equation is verified in the light of recent experimental information on masses and widths. The verification is carried out for the known level widths and the results came in support of the isobaric width equation removing all ...

A. M. Awin

1991-01-01

50

H-alpha Survey of the Local Volume: Isolated Southern Galaxies  

CERN Multimedia

We present our H-alpha observations of 11 isolated southern galaxies: SDIG, PGC 51659, E 222-010, E 272-025, E 137-018, IC 4662, Sag DIG, IC 5052, IC 5152, UGCA 438, and E149-003, with distances from 1 to 7 Mpc. We have determined the total H-alpha fluxes from these galaxies. The star formation rates in these galaxies range from 10^{-1} (IC 4662) to 10^{-4}_{\\odot}/yr (SDIG) and the gas depletion time at the observed star formation rates lies within the range from 1/6 to 24 Hubble times H_0^{-1} .

Kaisin, S S; Knyazev, A Yu; Karachentsev, I D

2007-01-01

51

Narrow H-alpha emission profiles in tokamaks: molecular origin and observational effects  

International Nuclear Information System (INIS)

The narrow hydrogen Balmer alpha profiles observed in tokamaks are explained in terms of the slow (approx. 0.3 eV) and fast (2 to 6 eV) excited atoms formed by dissociation of molecular hydrogen at the plasma edge. Extra widening of the spectrum in the wings can be explaind by Zeeman split H-alpha that is reflected from the vacuum vessel. This interpretation is consistent with available high-resolution data. The use of H-alpha as a diagnostic is discussed briefly

1981-01-01

52

Narrow H-alpha emission profiles in tokamaks: molecular origin and observational effects  

Energy Technology Data Exchange (ETDEWEB)

The narrow hydrogen Balmer alpha profiles observed in tokamaks are explained in terms of the slow (approx. 0.3 eV) and fast (2 to 6 eV) excited atoms formed by dissociation of molecular hydrogen at the plasma edge. Extra widening of the spectrum in the wings can be explaind by Zeeman split H-alpha that is reflected from the vacuum vessel. This interpretation is consistent with available high-resolution data. The use of H-alpha as a diagnostic is discussed briefly.

McNeill, D.H.

1981-04-01

53

First Simultaneous Observation of H-alpha Moreton Wave, EUV Wave, and Filament/Prominence Oscillations  

CERN Multimedia

We report on the first simultaneous observation of an H-alpha Moreton wave, the corresponding EUV fast coronal waves, and a slow and bright EUV wave (typical EIT wave). Associated with an X6.9 flare that occurred on 2011 August 9 at the active region NOAA 11263, we observed a Moreton wave in the H-alpha images taken by the Solar Magnetic Activity Research Telescope (SMART) at Hida Observatory of Kyoto University. In the EUV images obtained by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO) we found not only the corresponding EUV fast "bright" coronal wave, but also the EUV fast "faint" wave that is not associated with the H-alpha Moreton wave. We also found a slow EUV wave, which corresponds to a typical EIT wave. Furthermore, we observed, for the first time, the oscillations of a prominence and a filament, simultaneously, both in the H-alpha and EUV images. To trigger the oscillations by the flare-associated coronal disturbance, we expect a coronal wave as fast as the fast...

Asai, Ayumi; Isobe, Hiroaki; Kitai, Reizaburo; UeNo, Satoru; Nagata, Shin'ichi; Morita, Satoshi; Nishida, Keisuke; Shiota, Daikou; Oi, Akihito; Akioka, Maki; Shibata, Kazunari

2011-01-01

54

Early Results from the Wisconsin H-Alpha Mapper Southern Sky Survey  

CERN Document Server

After a successful eleven-year campaign at Kitt Peak, we moved the Wisconsin H-Alpha Mapper (WHAM) to Cerro Tololo in early 2009. Here we present some of the early data after a few months under southern skies. These maps begin to complete the first all-sky, kinematic survey of the diffuse H-alpha emission from the Milky Way. Much of this emission arises from the Warm Ionized Medium (WIM), a significant component of the ISM that extends a few kiloparsecs above the Galactic disk. While this first look at the data focuses on the H-alpha survey, WHAM is also capable of observing many other optical emission lines, revealing fascinating trends in the temperature and ionization state of the WIM. Our ongoing studies of the physical conditions of diffuse ionized gas will continue from the southern hemisphere following the H-alpha survey. In addition, future observations will cover the full velocity range of the Magellanic Stream, Bridge, and Clouds to trace the ionized gas associated with these neighboring systems.

Haffner, L M; Madsen, G J; Hill, A S; Barger, K A; Jaehnig, K P; Mierkiewicz, E J; Percival, J W; Chopra, N

2010-01-01

55

Scattered H-alpha emission from a large translucent cloud G294-24  

CERN Document Server

We study an undocumented large translucent cloud, detected by means of its enhanced radiation on the SHASSA (Southern H-Alpha Sky Survey Atlas) survey. We consider whether its excess surface brightness can be explained by light scattered off the dust grains in the cloud, or whether emission from in situ ionized gas is required. In addition, we aim to determine the temperature of dust, the mass of the cloud, and its possible star formation activity. We compare the observed H-alpha surface brightness of the cloud with predictions of a radiative transfer model. We use the WHAM (Wisconsin H-Alpha Mapper) survey as a source for the Galactic H-alpha interstellar radiation field illuminating the cloud. Visual extinction through the cloud is derived using 2MASS J, H, and K band photometry. We use far-IR ISOSS (ISO Serendipitous Survey), IRAS, and DIRBE data to study the thermal emission of dust. The LAB (The Leiden/Argentine/Bonn Galactic HI Survey) is used to study 21cm HI emission associated with the cloud. Radiati...

Lehtinen, K; Mattila, K

2010-01-01

56

Fabry-Perot H-alpha observations of Galactic H II regions  

International Nuclear Information System (INIS)

The radial velocity and linewidth of H-alpha emission from 284 objects listed in Galactic H II region catalogs were observed using a Fabry-Perot spectrometer. A few of these objects are supernova remnants or planetary nebula. The rest of this sample encompasses most of the H II regions that are visible optically from the Northern Hemisphere. These observations are compared to previous H-alpha observations as well as to radio recombination line and CO observations. The average radial-velocity difference V(CO) - V(H-alpha) is 0.50 + or - 0.48 km/s and the (1-sigma) dispersion is 6.44 km/s. The implications of these values are discussed in terms of a very simple kinematic and extinction H II region model. Total H-alpha luminosities for the sample are estimated, and the Galactic H II region luminosity function is compared to that recently found for other galaxies. 18 refs.

1990-01-01

57

H$\\alpha$ long term monitoring of the Be star $\\beta$ Cep Aa  

CERN Multimedia

Recent papers published in the last years contributed to resolve the enigma on the hypothetical Be nature of the hot pulsating star $\\beta$ Cep. This star shows variable emission in the H$\\alpha$ line, typical for Be stars, but its projected rotational velocity is very much lower than the critical limit, contrary to what is expected for a typical Be star. The emission has been attributed to the secondary component of the $\\beta$ Cep spectroscopic binary system. In this paper, using both ours and archived spectra, we attempted to recover the H$\\alpha$ profile of the secondary component and to analyze its behavior with time for a long period. To accomplish this task, we first derived the atmospheric parameters of the primary: T$_{\\rm eff}$ = 24000 $\\pm$ 250 K and $\\log g$ = 3.91 $\\pm$ 0.10, then we used these values to compute its synthetic H$\\alpha$ profile and finally we reconstructed the secondary's profile disentangling the observed one. The secondary's H$\\alpha$ profile shows the typical two peaks emission...

Catanzaro, G

2008-01-01

58

Study of flare buildup from simultaneous observations in microwave, H-alpha, and UV wavelengths  

International Nuclear Information System (INIS)

The results of high-resolution observations of the solar preflare activity of June 25, 1980 are analyzed. The observations were carried out simultaneously in the UV microwave, and H-alpha wavelengths using the VLA, the Ottawa River photoheliograph, and the Solar Max spectrometer and polarimeter instruments. Increases were observed in the intensitiy and polarization of compact sources at a wavelength of 6-cm during the preflare hour. The increases were associated with rising and twisting motions in the magnetic loops near the sight of the subsequent flare. Consistent with this process, analysis of the transverse and Doppler motions observed in the H-alpha filament before disruption showed that the filament was activated internally by the motions of evolving magnetic flux patterns. Ultraviolet data for C IV brightenings and upflows at the first appearance of the H-alpha filament indicated the presence of rising magnetic loops and material rising within the loops. The complete VLA, microwave and H-alpha data sets are given. 30 references.

1985-01-01

59

A study of flare buildup from simultaneous observations in microwave, H-alpha, and UV wavelengths  

Science.gov (United States)

The results of high-resolution observations of the solar preflare activity of June 25, 1980 are analyzed. The observations were carried out simultaneously in the UV microwave, and H-alpha wavelengths using the VLA, the Ottawa River photoheliograph, and the Solar Max spectrometer and polarimeter instruments. Increases were observed in the intensitiy and polarization of compact sources at a wavelength of 6-cm during the preflare hour. The increases were associated with rising and twisting motions in the magnetic loops near the sight of the subsequent flare. Consistent with this process, analysis of the transverse and Doppler motions observed in the H-alpha filament before disruption showed that the filament was activated internally by the motions of evolving magnetic flux patterns. Ultraviolet data for C IV brightenings and upflows at the first appearance of the H-alpha filament indicated the presence of rising magnetic loops and material rising within the loops. The complete VLA, microwave and H-alpha data sets are given.

Kundu, M. R.; Gaizauskas, V.; Woodgate, B. E.; Schmahl, E. J.; Shine, R.; Jones, H. P.

1985-03-01

60

H alpha Star Formation Rates in Massive Galaxies at z ~ 1  

CERN Multimedia

We present a near-infrared spectroscopic study of a stellar mass selected sample of galaxies at z~1 utilising the LIRIS multi-object spectrograph on the WHT. We detect continuum, and the H alpha line for our sample, which is one of the better direct tracers of star formation in external galaxies. We spectroscopically measure the H alpha emission from 41 massive (M_{*}>10^{10.5} Msol) galaxies taken from the POWIR Survey with spectroscopic redshifts 0.410^{11} Msol which are detected in H alpha emission at z<0.9. We furthermore find that the fraction of galaxies with H alpha emission drops steadily and significantly with redder (U-B) colours at z~1, and that the SSFR drops with increasing (U-B) colour for galaxies at all masses. By investigating the SFR-mass relation we find that the SFR is roughly constant with mass, in possible contrast to previous work, and that the specific star formation rate (SSFR) is lower in the most massive galaxies. The scatter in the SFR vs. mass relationship is very small for th...

Twite, Jonathan W; Buitrago, Fernando; Noeske, Kai; Weiner, Benjamin J; Acosta-Pulido, Jose A; Bauer, Amanda E

2011-01-01

 
 
 
 
61

On Jordanian $U_{h,\\alpha}(gl(2))$ Algebra and Its $T$ Matrices Via a Contraction Method  

CERN Multimedia

The $R_h^{j_1;j_2}$ matrices of the Jordanian U$_h$(sl(2)) algebra at arbitrary dimensions may be obtained from the corresponding $R_q^{j_1;j_2}$ matrices of the standard $q$-deformed U$_q$(sl(2)) algebra through a contraction technique. By extending this method, the coloured two-parametric ($h, \\alpha$) Jordanian $R_{h,\\alpha}^{j_1,z_1;j_2,z_2}$ matrices of the U$_{h,\\alpha}$(gl(2)) algebra may be derived from the corresponding coloured $R_{q,\\lambda}^{j_1,z_1;j_2,z_2}$ matrices of the standard ($q, contraction process as a tool, the coloured $T_{h,\\alpha}^{j,z}$ matrices for arbitrary ($j, z$) representations of the Jordanian Fun$_{h,\\alpha}$(GL(2)) algebra may be extracted from the corresponding $T_{q,\\lambda}^{j,z}$ matrices of the standard Fun$_{q,\\lambda}$(GL(2)) algebra.

Chakrabarti, R

1999-01-01

62

Using the Tremaine-Weinberg method to measure pattern speeds from H\\alpha velocity maps  

CERN Multimedia

The Tremaine-Weinberg method is a well-known model independent technique for measuring density wave pattern speeds in spiral galaxies. Here we show how it can be applied to the data cubes (maps of surface brightness and velocity) obtained in H-alpha emission using a Fabry-Perot spectrometer. One of the main difficulties, the discontinuity of the H-alpha emission, is resolved using the neighbouring stellar continuum delivered by the data cube. We argue from symmetry that the motions not associated with the density wave should cancel. We show that our pattern speeds are reasonable by computing corotation radii, and comparing them to measured bar lengths. Simulations including star forming gas also add credibility to our results. Nevertheless it will be necessary to compare them with results using the spectra of the stellar components to quantify any systematic deviations from valid pattern speed values.

Beckman, John; Piñol, Nuria; Hernandez, Olivier; Carignan, Claude; Pérez, Isabel

2008-01-01

63

Automated Detection of Filaments and their Disappearance using Full Disc H-alpha Images  

CERN Multimedia

A new algorithm is developed that automatically detects filaments on the solar disc in H-alpha images. Preprocessing of H-alpha images include corrections for limb darkening and foreshortening. Further, by applying suitable intensity and size thresholds, filaments are extracted, while other solar features e.g. sunspots and plages are removed. Filaments attributes such as their position on the solar disc, total area, length, and number of fragments are determined. In addition, every filament is also labelled with a unique number. The algorithm is capable of following a particular filament through successive images which allows us to detect the changes and disappearance of the same, and thus provides a real-time warning of eruptive filaments. This aspect would prove to be of particular importance in studies pertaining to space weather. The algorithm will eventually be integrated with an upcoming telescope at Udaipur Solar Observatory for real time monitoring of activated/eruptive filaments.

Joshi, Anand D; Mathew, Shibu K

2009-01-01

64

Constraints on supernova progenitors from spatial correlations with H-alpha emission  

CERN Document Server

We have attempted to constrain the progenitors of all supernova types, through correlations of the positions of historical supernovae with recent star formation, as traced by H-alpha emission. Through pixel statistics we have found that a large fraction of the SNII population do not show any association with current star formation, which we put down to a 'runaway' fraction of these progenitors. The SNIb/c population accurately traces the H-alpha emission, with some suggestion that the SNIc progenitors show a higher degree of correlation than the SNIb, suggesting higher mass progenitors for the former. Overall the SNIa population only show a weak correlation to the positions of HII regions, but as many as a half may be associated with a young stellar population.

Anderson, J P; Salaris, M; Percival, S M

2007-01-01

65

Deconvolution of H-alpha profiles measured by Thompson scattering collecting optics  

International Nuclear Information System (INIS)

This paper discusses that optically fast multichannel Thomson scattering optics that can be used for H-alpha emission profile measurement. A technique based on the fact that a particular volume element of the overall field of view can be seen by many channels, depending on its location, is discussed. It is applied to measurement made on PDX with the vertically viewing TVTS collecting optics (56 channels). The authors found that for this case, about 28 Fourier modes are optimum to represent the spatial behavior of the plasma emissivity. The coefficients for these modes are obtained by doing a least-square-fit to the data subjet to certain constraints. The important constraints are non-negative emissivity, the assumed up and down symmetry and zero emissivity beyond the liners. H-alpha deconvolutions are presented for diverted and circular discharges.

1986-01-01

66

Using H-alpha as a Tracer of the Emission Region of LS I +61 303  

CERN Document Server

The gamma-ray binary LS I +61 303 is one of the brightest Fermi sources, with orbitally modulated emission across the electromagnetic spectrum. Here we present H-alpha spectra of LS I +61 303 that exhibit a dramatic emission burst shortly before apastron, observed as a redshifted shoulder in the line profile. A correlated burst in radio, X-ray, and GeV emission is observed at the same orbital phase. We interpret the source of the emission as a compact pulsar wind nebula that forms when a tidal mass stream from the Be circumstellar disk interacts with the relativistic pulsar wind. The H-alpha emission offers an important probe of the high energy emission morphology in this system.

McSwain, M Virginia

2011-01-01

67

Variations of flaring kernel sizes in various parts of the H-alpha line profile  

CERN Multimedia

We analyze the temporal variations of the sizes and emission intensities of thirtyone flaring kernels in various parts of the H{\\alpha} line profile. We have found that the areas of all kernels decrease systematically when observed in consecutive wavelengths toward the wings of the H{\\alpha} line, but their areas and emission intensity vary in time. Our results are in agreement with the commonly accepted model of the glass-shaped lower parts of the magnetic flaring loops channelling high energy variable particle beams toward the chromospheric plasma. High time resolution spectral-imaging data used in our work were collected using the Large Coronagraph and Horizontal Telescope equipped with the Multi-channel Subtractive Double Pass Spectrograph and the Solar Eclipse Coronal Imaging System (MSDP-SECIS) at the Bia{\\l}k\\'ow Observatory of the University of Wroc{\\l}aw, Poland.

Radziszewski, K

2012-01-01

68

An observational limit on circumstellar H-alpha from supernova 1994D  

CERN Document Server

We searched for narrow H\\alpha in a high-resolution spectrum of SN 1994D taken 10 days before maximum, and found none. We estimate the limit this places on the progenitor mass loss, and find that it is competitive with recent radio limits, and excludes the highest-mass-loss-rate symbiotic systems as possible progenitors of the normal Type Ia SN 1994D.

Cumming, R J; Smith, L J; Pettini, M; King, D L

1995-01-01

69

H-alpha confirmation of two recent disc novae in M 31  

Science.gov (United States)

We obtained a set of 11x180s, 11x120s, and 11x60s dithered stacked CCD images of M 31, respectively, using Baader broad (7nm wide) H-alpha, Baader R and Baader clear (Cl) filters on 2011 July 5 with the Open University PIRATE Planewave CDK17 0.43m Dall-Kirkham f/6.7 telescope at the Observatorio Astronomico de Mallorca, Costitx, Spain, using an SBIG STX 16803 CCD Camera.

Burwitz, V.; Henze, M.; Pietsch, W.; Holmes, S.; Kolb, U.; Rodriguez, C. A. Haswell J.

2011-07-01

70

An H-alpha nuclear spiral structure in the E0 active galaxy Arp102B  

CERN Document Server

We report the discovery of a two-armed mini-spiral structure within the inner kiloparsec of the E0 LINER/Seyfert 1 galaxy Arp102B. The arms are observed in H-alpha emission and located East and West of the nucleus, extending up to about 1 kpc from it. We use narrow-band imaging from the Hubble Space Telescope Advanced Camera for Surveys, in combination with archival VLA radio images at 3.6 and 6 cm to investigate the origin of the nuclear spiral. From the H-alpha luminosity of the spiral, we obtain an ionized gas mass of the order of one million solar masses. One possibility is that the nuclear spiral represents a gas inflow triggered by a recent accretion event which has replenished the accretion disk, giving rise to the double-peaked emission-line profiles characteristic of Arp102B. However, the radio images show a one-sided curved jet which correlates with the eastern spiral arm observed in the H-alpha image. A published milliarcsecond radio image also shows one-sided structure at position angle about 40 d...

Fathi, Kambiz; Storchi-Bergmann, Thaisa; Kharb, Preeti; Robinson, Andrew; Marconi, Alessandro; Maciejewski, Witold; Capetti, Alessandro

2011-01-01

71

On the H$\\alpha$ emission from the $\\beta$ Cephei system  

CERN Multimedia

Be stars, which are characterised by intermittent emission in their hydrogen lines, are known to be fast rotators. This fast rotation is a requirement for the formation of a Keplerian disk, which in turn gives rise to the emission. However, the pulsating, magnetic B1IV star $\\beta$ Cephei is a very slow rotator that still shows H$\\alpha$ emission episodes like in other Be stars, contradicting current theories. We investigate the hypothesis that the H$\\alpha$ emission stems from the spectroscopically unresolved companion of $\\beta$ Cep. Spectra of the two unresolved components have been separated in the 6350-6850\\AA range with spectro-astrometric techniques, using 11 longslit spectra obtained with ALFOSC at the Nordic Optical Telescope, La Palma. We find that the H$\\alpha$ emission is not related to the primary in $\\beta$ Cep, but is due to its 3.4 magnitudes fainter companion. This companion has been resolved by speckle techniques, but it remains unresolved by traditional spectroscopy. The emission extends fr...

Schnerr, R S; Oudmaijer, R D; Telting, J H

2006-01-01

72

The star formation properties of disk galaxies H $\\alpha$ imaging of galaxies in the Coma supercluster  

CERN Multimedia

We present integrated H alpha measurements obtained from imaging observations of 98 late-type galaxies, primarily selected in the Coma supercluster. These data, combined with H alpha photometry from the literature, include a magnitude selected sample of spiral (Sa to Irr) galaxies belonging to the "Great Wall" complete up to mp=15.4, thus composed of galaxies brighter than Mp=-18.8 (H0=100 km Mpc^-1 s^-1). The frequency distribution of the H alpha E.W., determined for the first time from an optically complete sample, is approximately gaussian peaking at E.W. ~25 A. We find that, at the present limiting luminosity, the star formation properties of spiral+Irr galaxies members of the Coma and A1367 clusters do not differ significantly from those of the isolated ones belonging to the Great Wall. The present analysis confirms the well known increase of the current massive star formation rate (SFR) with Hubble type. Moreover perhaps a more fundamental anticorrelation exists between the SFR and the mass of disk gala...

Gavazzi, G; Carrasco, L; Boselli, A; Contursi, A

1998-01-01

73

The SINS Survey: Broad H-alpha Emission in High-Redshift Star-Forming Galaxies  

CERN Multimedia

High signal-to-noise, representative spectra of star-forming galaxies at z~2, obtained via stacking of the galaxies observed in the context of the SINS survey, reveal broad (FWHM > 1500 km/s) H-alpha emission. This feature is preferentially found in the more massive and more rapidly star-forming systems, which also tend to be older and larger galaxies. We interpret this feature as evidence of either powerful starburst-driven galactic winds or active supermassive black holes. If galactic winds are responsible for the broad H-alpha emission, the high velocities of this ionized gas indicate that much of it will be expelled from the host galaxy and its dark matter halo. On the other hand, if the broad line regions of active black holes account for the broad H-alpha feature, the corresponding black holes masses are estimated to be an order of magnitude lower than those predicted by local scaling relations, suggesting a delayed assembly of supermassive black holes with respect to their host bulges.

Shapiro, Kristen L; Quataert, Eliot; Schreiber, Natascha M Förster; Davies, Richard; Tacconi, Linda; Armus, Lee; Bouché, Nicolas; Buschkamp, Peter; Cimatti, Andrea; Cresci, Giovanni; Daddi, Emanuele; Eisenhauer, Frank; Erb, Dawn K; Genel, Shy; Hicks, Erin K S; Lilly, Simon J; Lutz, Dieter; Renzini, Alvio; Shapley, Alice; Steidel, Charles C; Sternberg, Amiel

2009-01-01

74

MASH-II: More Planetary Nebulae from the AAO/UKST H\\alpha Survey  

CERN Multimedia

We present a supplement to the Macquarie/AAO/Strasbourg H$\\alpha$ planetary nebulae (PNe) catalogue (MASH), which we denote MASH-II. The supplement consists of over 300 true, likely and possible new Galactic PNe found after re-examination of the entire AAO/UKST H$\\alpha$ survey of the southern Galactic Plane in digital form. We have spectroscopically confirmed over 240 of these new candidates as bona-fide PNe and we include other high quality candidates awaiting spectroscopic confirmation as possible PNe. These latest discoveries largely comprise two distinct groups: small, star-like or moderately resolved PNe at one end and mostly large, extremely low surface brightness PNe at the other. Neither group were easy to discover from simple visual scrutiny of the original survey exposures as for MASH but were relatively straightforward to uncover from the digital images via application of semi-automated discovery techniques. We suspect the few PNe still hidden in the H$\\alpha$ survey will lie outside our search cr...

Miszalski, B; Acker, A; Birkby, J L; Frew, D J; Kovacevic, A

2007-01-01

75

The $H\\alpha$ emission of the spiral galaxy NGC 7479  

CERN Document Server

We use the catalogue of HII regions obtained from a high quality continuum-subtracted H$\\alpha$ image of the grand design spiral galaxy NGC 7479, to construct the luminosity function (LF) for the HII regions (over 1000) of the whole galaxy. Although its slope is within the published range for spirals of the same morphological type, the unusually strong star formation along the intense bar of NGC 7479 prompted us to analyze separately the HII regions in the bar and in the disc. We have calculated the physical properties of a group of HII regions in the bar and in the disc selected for their regular shapes and absence of blending. We have obtained galaxy-wide relations for the HII region set: diameter distribution function and also the global H$\\alpha$ surface density distribution. As found previously for late-type spirals, the disc LF shows clear double-linear behaviour with a break at log L$_{H\\alpha}$=38.6 (in erg/s). The bar LF is less regular. This reflects a physical difference between the bar and the dis...

Zurita, A; Beckman, J E; Zurita, Almudena; Rozas, Maite; Beckman, John E.

1999-01-01

76

Observational and theoretical constraints for an H$\\alpha$-halo around the Crab Nebula  

CERN Document Server

We searched for a fast moving H$\\alpha$ shell around the Crab nebula. Such a shell could account for this supernova remnant's missing mass, and carry enough kinetic energy to make SN 1054 a normal Type II event. Deep H$\\alpha$ images were obtained with WFI at the 2.2m MPG/ESO telescope and with MOSCA at the 2.56m NOT. The data are compared with theoretical expectations derived from shell models with ballistic gas motion, constant temperature, constant degree of ionisation and a power law for the density profile. We reach a surface brightness limit of $5\\times10^{-8} ergs s^{-1} cm^{-2} sr^{-1}$. A halo is detected, but at a much higher surface brightness than our models of recombination emission and dust scattering predict. Only collisional excitation of Ly$\\beta$ with partial de-excitation to H$\\alpha$ could explain such amplitudes. We show that the halo seen is due to PSF scattering and thus not related to a real shell. We also investigated the feasibility of a spectroscopic detection of high-velocity H$\\al...

Tziamtzis, A; Lundqvist, P; Sollerman, J

2009-01-01

77

The H-alpha Variations of eta Carinae During the 2009.0 Spectroscopic Event  

CERN Multimedia

We report on H-alpha spectroscopy of the 2009.0 spectroscopic event of eta Carinae collected via SMARTS observations using the CTIO 1.5 m telescope and echelle spectrograph. Our observations were made almost every night over a two month interval around the predicted minimum of eta Car. We observed a significant fading of the line emission that reached a minimum seven days after the X-ray minimum. About 17 d prior to the H-alpha flux minimum, the H-alpha profile exhibited the emergence of a broad, P Cygni type, absorption component (near a Doppler shift of -500 km/s) and a narrow absorption component (near -144 km/s and probably associated with intervening gas from the Little Homunculus Nebula). All these features were observed during the last event in 2003.5 and are probably related to the close periastron passage of the companion. We argue that these variations are consistent with qualitative expectations about changes in the primary star's stellar wind that result from the wind-wind collision with a massive...

Richardson, N D; Henry, T J; Fernandez-Lajus, E; Okazaki, A T

2010-01-01

78

Is the Broad-Line Region Clumped or Smooth? Constraints from the H alpha Profile in NGC 4395, the Least Luminous Seyfert 1 Galaxy  

CERN Multimedia

The origin and configuration of the gas which emits broad lines in Type I active galactic nuclei is not established yet. The lack of small-scale structure in the broad emission-line profiles is consistent with a smooth gas flow, or a clumped flow with many small clouds. An attractive possibility for the origin of many small clouds is the atmospheres of bloated stars, an origin which also provides a natural mechanism for the cloud confinement. Earlier studies of the broad-line profiles have already put strong lower limits on the minimum number of such stars, but these limits are sensitive to the assumed width of the lines produced by each cloud. Here we revisit this problem using high-resolution Keck spectra of the H alpha line in NGC 4395, which has the smallest known broad-line region (~10^14 cm). Only a handful of the required bloated stars (each having r~10^14 cm) could fit into the broad-line region of NGC 4395, yet the observed smoothness of the H alpha line implies a lower limit of ~10^4-10^5 on the num...

Laor, A; Ho, L C; Filippenko, A V; Laor, Ari; Barth, Aaron J.; Ho, Luis C.; Filippenko, Alexei V.

2005-01-01

79

Equivalent widths of 9 stars of M 67 (Tautvaisiene+, 2000)  

Science.gov (United States)

High-resolution spectra of six core helium-burning `clump' stars and three giants in the open cluster M 67 have been obtained with the SOFIN spectrograph on the Nordic Optical Telescope to investigate abundances of up to 25 chemical elements. Abundances of carbon were studied using the C2 Swan (0,1) band head at 5635.5Å. The wavelength interval 7980-8130Å with strong CN features was analysed in order to determine nitrogen abundances and 12C/13C isotope ratios. The oxygen abundances were determined from the [O I] line at 6300Å. The overall metallicity of the cluster stars was found to be close to solar ([Fe/H]=-0.03+/-0.03). Compared with the Sun and other dwarf stars of the Galactic disk, as well as with dwarf stars of M 67 itself, abundances in the investigated stars suggest that carbon is depleted by about 0.2dex, nitrogen is enhanced by about 0.2dex and oxygen is unaltered. Among other mixing-sensitive chemical elements an overabundance of sodium may be suspected. The mean C/N and 12C/13C ratios are lowered to the values of 1.7+/-0.2 and 24+/-4 in the giants and to the values of 1.4+/-0.2 and 16+/-4 in the clump stars. These results suggest that extra mixing of CN-cycled material to the stellar surface takes place after the He-core flash. Abundances of heavy chemical elements in all nine stars were found to be almost identical and close to solar. (2 data files).

Tautvaisiene, G.; Edvardsson, B.; Tuominen, I.; Ilyin, I.

2000-08-01

80

Equivalent widths for 6 RS CVn systems (Morel+, 2003)  

Science.gov (United States)

The spectra were acquired in January 2000 at the ESO 1.52-m telescope (La Silla, Chile) with the fiber-fed, cross-dispersed echelle spectrograph FEROS in the object+sky configuration. The atomic data have been calibrated using a high S/N moonlight spectrum extracted from the archive of the first FEROS commissioning period (fall 1998). (1 data file).

Morel, T.; Micela, G.; Favata, F.; Katz, D.; Pillitteri, I.

2003-11-01

 
 
 
 
81

Optical Observations of M81 Galaxy Group in Narrow Band [SII] and H_alpha Filters: Holmberg IX  

Directory of Open Access Journals (Sweden)

Full Text Available We present observations of the nearby tidal dwarf galaxy Holmberg IX in M81 galaxy group in narrow band [SII] and H$alpha$ filters, carried out in March and November 2008 with the 2m RCC telescope at NAO Rozhen, Bulgaria. Our search for resident supernova remnants (identified as sources with enhanced [SII] emission relative to their H$alpha$ emission) in this galaxy yielded no sources of this kind, besides M&H 10-11 or HoIX X-1. Nevertheless, we found a number of objects with significant H$alpha$ emission that probably represent uncatalogued HII regions.

Arbutina, B.; Ili?, D.; Stavrev, K.; Uroševi?, D.; Vukoti?, B.; Oni?, D.

2009-01-01

82

Auger widths of levels  

Energy Technology Data Exchange (ETDEWEB)

The partial Auger width corresponding to the transitions from the considered level to all levels of particular configuration is presented in the form of the diagonal matrix element of an effective operator. The general expressions for such an operator in the case of two main types of Auger transitions are obtained. They are used to derive the explicit formulae in some special cases as well as to investigate the term-dependence of the Auger width. The types of configurations which levels have equal Auger width or, on the contrary, strongly depend on many-electron quantum numbers, are indicated.

Merkelis, G. E-mail: merkelis@itpa.lt; Karazija, R

2003-11-01

83

Near- And Mid-Infrared Imaging Study of Young Stellar Objects around LkH$\\alpha$ 234  

CERN Document Server

We present high-resolution ($0\\farcs2$) near-infrared images of the area surrounding the Herbig Be star LkH$\\alpha$ 234 taken with the Coronagraphic Imager with Adaptive Optics (CIAO) and the adaptive optics on the Subaru Telescope. The near-infrared ($J$, $H$, $K$, $L'$ and $M'$ bands) images reveal circumstellar structures around LkH$\\alpha$ 234 in detail. Eight young stellar object (YSO) candidates (Object B, C, D, E, F, G, NW1, and NW2) were detected at 2$\\arcsec$--11$\\arcsec$ from LkH$\\alpha$ 234. Objects B and C are likely variable stars, which is consistent with a young evolutionary status. Three objects (LkH$\\alpha$ 234, NW1, and NW2) were identified in the 11.8 $\\micron$ (SiC) and 17.65 $\\micron$ images obtained with the Long Wavelength Spectrometer (LWS) on the Keck Telescope. NW1 and NW2 are thought to be embedded young stars. We suggest that NW1 and not LkH$\\alpha$ 234 is the source illuminating the reflection nebula west of LkH$\\alpha$ 234, although Object G may be another candidate. In our image...

Kato, Eri; Perrin, Marshall D; Shibai, Hiroshi; Itoh, Yusuke; Ootsubo, Takafumi

2011-01-01

84

Graphs of Small Rank-width are Pivot-minors of Graphs of Small Tree-width  

CERN Document Server

We prove that every graph of rank-width $k$ is a pivot-minor of a graph of tree-width at most $2k$. We also prove that graphs of rank-width at most 1, equivalently distance-hereditary graphs, are exactly vertex-minors of trees, and graphs of linear rank-width at most 1 are precisely vertex-minors of paths. In addition, we show that bipartite graphs of rank-width at most 1 are exactly pivot-minors of trees and bipartite graphs of linear rank-width at most 1 are precisely pivot-minors of paths.

Kwon, O-joung

2012-01-01

85

H{\\alpha} Kinematics of S4G spiral galaxies I. NGC 864  

CERN Multimedia

We present a study of the kinematics of the isolated spiral galaxy NGC 864, using H{\\alpha} Fabry-Perot data obtained with the GH{\\alpha}FaS instrument at the William Herschel Telescope in La Palma, complemented with images at 3.6 {\\mu}m, in the R band and in H{\\alpha} filter, and integral field spectroscopic data. The resulting data cubes and velocity maps allow the study of the kinematics of the galaxy, including in-depth investigations of the rotation curve, velocity moment maps, velocity residual maps, gradient maps and position-velocity diagrams. We find asymmetries in the velocity field in the bar zone, caused by non-circular motions, probably in response to the potential of the bar. We also find a flat-profile bar, in agreement with the strong bar, with the grand design spiral pattern, and with the gap between the ends of the bar and the start of the spiral arms. We quantify the rate of massive star formation, which is concentrated in the two spiral arms.

Erroz-Ferrer, Santiago; Font, Joan; Beckman, John E; Falcón-Barroso, Jesús; Sánchez-Gallego, José Ramón; Athanassoula, E; Bosma, Albert; Gadotti, Dimitri A; Muñoz-Mateos, Juan Carlos; Sheth, Kartik; Buta, Ronald J; Comerón, Sébastien; de Paz, Armando Gil; Hinz, Joannah L; Ho, Luis C; Kim, Taehyun; Laine, Jarkko; Laurikainen, Eija; Madore, Barry F; Menéndez-Delmestre, Karín; Mizusawa, Trisha; Regan, Michael W; Salo, Heikki; Seibert, Mark

2012-01-01

86

The H alpha Galaxy Survey. IV. Star formation in the local Universe  

CERN Multimedia

We present an analysis of the star formation properties of field galaxies within the local volume out to a recession velocity limit of 3000 km/s. A parent sample of 863 star-forming galaxies is used to calculate a B-band luminosity function. This is then populated with star formation information from a subsample of 327 galaxies, for which we have H alpha imaging, firstly by calibrating a relationship between galaxy B-band luminosity and star formation rate, and secondly by a Monte Carlo simulation of a representative sample of galaxies, in which star formation information is randomly sampled from the observed subset. The total star formation rate density of the local Universe is found to be between 0.016 and 0.023 MSun/yr/cubic Mpc, with the uncertainties being dominated by the internal extinction correction used in converting measured H alpha fluxes to star formation rates. If our internally derived B-band luminosity function is replaced by one from the Sloan Digital Sky Survey blue sequence, the star format...

James, P A; Shane, N S; Baldry, I K; De Jong, R S

2008-01-01

87

Deep H{\\alpha} Observations of NGC 253: a Very Extended and Possibly Declining Rotation Curve?  

CERN Multimedia

This study presents a deep H{\\alpha} kinematical analysis of the Sculptor Group galaxy NGC253. The Fabry-Perot data were taken with the 36-cm Marseille Telescope in La Silla, Chile, using an EMCCD detector. Typical emission measures of ~0.1 cm^-6 pc are reached. The observations allow the detection of the Diffuse Ionized Gas component through [N II] emission at very large radii of 11.5', 12.8' and 19.0', on the receding side of the galaxy. No H{\\alpha} emission is observed at radii larger than the neutral component (11.5'). The very extended rotation curve confirms previous results and shows signs of a significant decline, on the order of 30 per cent vmax . Using the rotation data, mass models are constructed with and without the outer [N II] data points, and similar results are found. The declining part of the rotation curve is very well modeled, and seems to be truly declining.

Hlavacek-Larrondo, J; Daigle, O; de Denus-Baillargeon, M -M; Marcelin, M; Epinat, B; Hernandez, O

2010-01-01

88

Two-dimensional H_alpha kinematics of bulgeless disk galaxies  

CERN Document Server

We present two-dimensional H_alpha velocity fields for 20 late-type, disk-dominated spiral galaxies, the largest sample to date with high-resolution H_alpha velocity fields for bulgeless disks. From these data we derive rotation curves and the location of the kinematic centers. The galaxy sample was selected to contain nucleated and non-nucleated galaxies, which allows us to investigate what impact the gas kinematics in the host disk have on the presence (or absence) of a nuclear star cluster. In general, we find that the velocity fields span a broad range of morphologies. While some galaxies show regular rotation, most have some degree of irregular gas motions. There appears to be no systematic difference in the kinematics of nucleated and non-nucleated disks. Due to the large fields of view of the integral field units we use, we are able to observe the flattening of the rotation curve in almost all of our sample galaxies. This makes modeling of the velocity fields relatively straight-forward. Due to the com...

Neumayer, Nadine; Andersen, David; Sanchez, Sebastian F; Boeker, Torsten; Rix, Hans-Walter

2011-01-01

89

An H-alpha search for over-dense regions at z=2.23  

CERN Multimedia

We present the results of a narrow-band (H2S1, 2.121/0.021um) imaging search with WFCAM/UKIRT for H-alpha emitters around several potential signposts of rare (10^-7-10^-8 Mpc^-3) over-dense regions at z=2.23: an over-density of QSOs (2QZ cluster), a powerful, high-redshift radio galaxy (HzRG), and a concentration of submillimetre galaxies (SMGs) and optically faint radio galaxies (OFRGs). In total, we detect 137 narrow-band emitter candidates down to emission-line fluxes of 0.5-1 x 10^-16 erg s^-1 cm^-2, across a total area of 0.56 sq. degrees (2.1 x 10^5 comoving Mpc at z=2.23) in these fields. The BzK colours of the emitters suggest that at least 80% of our sample are likely to be H-alpha emitters (HAEs) at z=2.23. This is one of the largest HAE samples known at z>2. We find modest (~3-sigma) local over-densities of emitters associated with all the three targets. In the 2QZ cluster field, the emitters show a striking filamentary structure connecting four of the z=2.23 QSOs extending over 30Mpc (comoving). I...

Matsuda, Y; Geach, J E; Best, P N; Sobral, D; Tanaka, I; Ohta, K; Kurk, J; Iwata, I; Bielby, Rich; Wardlow, J L; Bower, R G; Fanidakis, N; Ivison, R J; Kodama, T; Yamada, T; Mawatari, K; Casali, M

2011-01-01

90

Star Formation at Redshift One: Preliminary results from an H-alpha Survey  

CERN Document Server

We present the first successful demonstration of multi-object near-infrared spectroscopy on high redshift galaxies. Our objective is to address the true star formation history of the universe at z~1, a crucial epoch which some have suggested is the peak of star formation activity. By using H-alpha -the same robust star formation indicator used at low-z - redshifted into the J- and H-bands, we can trace star formation without the systematic uncertainties of different calibrators, or the extreme dust extinction in the rest-UV, which have plagued previous efforts. We are using the instrument CIRPASS (the Cambridge Infra-Red PAnoramic Survey Spectrograph), in multi-object mode, which has been successfully demonstrated on the Anglo-Australian Telescope (AAT) and the William Herschel Telescope (WHT). CIRPASS has 150 fibres deployable over \\~40arcmin on the AAT and ~15arcmin on the WHT. Here we present preliminary results from one of our fields observed with the WHT: H-alpha detections of z~1 galaxies in the Hubble ...

Doherty, M; Sharp, R; Dalton, G B; Parry, I; Lewis, I; McDonald, E; Wolf, C

2004-01-01

91

A study of solar flare energy transport based on coordinated H-alpha and X-ray observations  

International Nuclear Information System (INIS)

The temporal evolution of the ratio between H-alpha to nonthermal hard X-ray emission was investigated using coordinated H-alpha and hard- and soft-X-ray observations of five solar flares (on May 7, June 23, June 24, and June 25, 1980 and on April 30, 1985). These observations were used to estimate the emitted flare energy flux F(H-alpha) in H-alpha, the flux of F(2O) energy deposited by nonthermal electrons with energies above 20 keV, and the pressure p(c) of soft X-ray-emitting plasma as functions of time during the impulsive phase of each flare. It was found that the F(H-alpha)/F(2O) ratio shows a power-law dependence on F(2O), with a slope that differs slightly from that predicted by the static thick-target model of solar transport. Results also indicate that the power-law dependence is modified by hydrostatic pressure effects. 25 refs.

1991-01-01

92

Massive starburst galaxies in a z=2.16 proto-cluster unveiled by panoramic H-alpha mapping  

CERN Document Server

We present a panoramic narrow-band study of H-alpha emitters in the field of the z=2.16 proto-cluster around PKS1138-262 using MOIRCS on the Subaru Telescope. We find 83 H-alpha emitters down to a SFR(Ha)~10Msun/yr across a ~7'x7' region centered on the radio galaxy, and identify ~10-Mpc scale filaments of emitters running across this region. By examining the properties of H-alpha emitters within the large-scale structure, we find that galaxies in the higher-density environments at z=2.16 tend to have redder colours and higher stellar masses compared to galaxies in more underdense regions. We also find a population of H-alpha emitters with red colours ((J-Ks)>1), which are much more frequent in the denser environments and which have apparently very high stellar masses with M*>~10^11Msun, implying that these cluster galaxies have already formed a large part of their stellar mass before z~2. Spitzer Space Telescope 24-micron data suggests that many of these red H-alpha emitters are bright, dusty starbursts (rat...

Koyama, Yusei; Tadaki, Ken-ichi; Hayashi, Masao; Tanaka, Masayuki; Smail, Ian; Tanaka, Ichi; Kurk, Jaron

2012-01-01

93

Comportamiento de la cromósfera solar en la línea H-alpha durante el ciclo 23  

Science.gov (United States)

Using the instrumental of the Observatorio Astronómico Municipal de Rosario (OAMR), we analyze the solar chromospheric activity during an approximate period of 11 years. The instrument is a Carl Zeiss refractor telescope of 150 mm aperture and 2250 mm of focal distance with monochromatic filter in the H-alpha line. We take as proxy for the solar activity the area covered by chromospheric plages. Simultaneously, we determine the relative wolf number from observations of the solar photosphere. We describe our technique and the results obtained. We observe 2 maxima of solar activity in the years 2000 and 2001 respectively, and a later decrease of this activity with low average values starting around 2006 that corresponds to the end of cycle 23. FULL TEXT IN SPANISH

Davoli, D.; Aquilano, R.; Missio, H.

94

Spectroscopic identifications of blue H-alpha excess sources in the Kepler field-of-view  

CERN Multimedia

We present the first results of an ongoing spectroscopic follow-up program of blue H-alpha excess sources within the Kepler field-of-view, in order to identify new cataclysmic variables. Kepler observations of the identified targets in this work will then provide detailed, time-resolved, studies of accretion. Candidates selected from the Kepler-INT Survey were observed with the 4.2 meter William Herschel Telescope. Out of 38 observed candidates, we found 11 new cataclysmic variables reported here for the first time, as well as 13 new quasars. Our target selection has a success rate of 29% when searching for cataclysmic variables, and we show how this can be improved by including photometry obtained with the Wide-field Infrared Survey Explorer.

Scaringi, S; Verbeek, K; Greiss, S; Knigge, C; Koerding, E

2012-01-01

95

H-alpha detection of seven recent optical novae in M 31  

Science.gov (United States)

We report the detection of seven recent nova candidates in M 31 on two sets of three 300 s dithered stacked CCD images obtained on 2010 Oct 4 with the 1.3m Ritchey Chretien f/7.5 telescope at Skinakas Observatory, Crete, Greece, using an Andor DZ436-BV CCD Camera (with a Marconi 2k x 2k chip with 13.5 microns sq. pixels) and a broad (75 Angstrom wide) H-alpha filter. Only novae M31N 2010-07a and M31N 2010-10a were also detected on four 100 s dithered stacked CCD images obtained on 2010 Oct 5 with the same telescope and camera using a R filter.

Pietsch, W.; Lloyd, J.; Henze, M.; Burwitz, V.; Liakos, A.; Hatzidimitriou, D.

2010-10-01

96

The star formation rate at redshift one: H-alpha spectroscopy with CIRPASS  

CERN Document Server

We have conducted an H-alpha survey of 38 0.77

Doherty, M; Dalton, G; Lewis, I; Parry, I; Sharp, R; Bunker, Andrew; Dalton, Gavin; Doherty, Michelle; Lewis, Ian; Parry, Ian; Sharp, Robert

2006-01-01

97

Chromospheric Sunspot Oscillations in H-alpha and Ca II 8542A  

CERN Multimedia

We study chromospheric oscillations including umbral flashes and running penumbral waves in a sunspot of active region (AR) using scanning spectroscopy in H-alpha and Ca II 8542A, with the Fast Imaging Solar Spectrograph (FISS) at the 1.6 meter New Solar Telescope at Big Bear Solar Observatory. A bisector method is applied to spectral observations to construct chromospheric Doppler velocity maps. Temporal sequence analysis of these shows enhanced high-frequency oscillations inside the sunspot umbra in both lines. Their peak frequency gradually decreases outward from the umbra. The oscillation power is found to be associated with magnetic-field strength and inclination, with different relationships in different frequency bands.

Maurya, Ram Ajor; Park, Hyungmin; Yang, Heesu; Song, Donguk; Cho, Kyuhyoun

2013-01-01

98

Study of the {sup 2}H({alpha},{gamma}){sup 6}Li reaction at LUNA  

Energy Technology Data Exchange (ETDEWEB)

Observations of very metal poor stars have yielded evidence for the less abundant lithium isotope {sup 6}Li in several cases. These findings prompt the question whether there is a non-negligible primordial contribution to the observed {sup 6}Li abundances. Network calculations show that the {sup 2}H({alpha},{gamma}){sup 6}Li reaction dominates {sup 6}Li production in the Big Bang. A recent Coulomb dissociation work on this reaction produced only an upper limit for the astrophysical S-factor. At the 400 kV underground accelerator LUNA in Gran Sasso/Italy, an experiment is underway to gain direct cross section data, but the background is formidable. Preliminary data of the first phase of the LUNA experiment will be shown, and an outlook will be given.

Anders, Michael; Bemmerer, Daniel [Forschungszentrum Dresden-Rossendorf (FZD), Dresden (Germany); Collaboration: LUNA-Collaboration

2011-07-01

99

Comparison of H-alpha and UV Star Formation Rates in the Local Volume: Systematic Discrepancies for Dwarf Galaxies  

CERN Multimedia

(abridged) Using a complete sample of ~300 star-forming galaxies within 11 Mpc, we evaluate the consistency between star formation rates (SFRs) inferred from the far ultraviolet (FUV) non-ionizing continuum and H-alpha nebular emission, assuming standard conversion recipes in which the SFR scales linearly with luminosity at a given wavelength. Our analysis probes SFRs over 5 orders of magnitude, down to ultra-low activities on the order of ~0.0001 M_sun/yr. The data are drawn from the 11 Mpc H-alpha and Ultraviolet Galaxy Survey (11HUGS), which has obtained H-alpha fluxes from ground-based narrowband imaging, and UV fluxes from imaging with GALEX. For normal spiral galaxies (SFR~1 M_sun/yr), our results are consistent with previous work which has shown that FUV SFRs tend to be lower than H-alpha SFRs before accounting for internal dust attenuation, but that there is relative consistency between the two tracers after proper corrections are applied. However, a puzzle is encountered at the faint end of the lumin...

Lee, Janice C; Tremonti, Christy; Kennicutt, Robert C; Salim, Samir; Bothwell, Matthew; Calzetti, Daniela; Dalcanton, Julianne; Dale, Daniel; Engelbracht, Chad; J., Jose G Funes S; Johnson, Benjamin; Sakai, Shoko; Skillman, Evan; van Zee, Liese; Walter, Fabian; Weisz, Daniel

2009-01-01

100

FIRST SIMULTANEOUS OBSERVATION OF AN H{alpha} MORETON WAVE, EUV WAVE, AND FILAMENT/PROMINENCE OSCILLATIONS  

Energy Technology Data Exchange (ETDEWEB)

We report on the first simultaneous observation of an H{alpha} Moreton wave, the corresponding EUV fast coronal waves, and a slow and bright EUV wave (typical EIT wave). We observed a Moreton wave, associated with an X6.9 flare that occurred on 2011 August 9 at the active region NOAA 11263, in the H{alpha} images taken by the Solar Magnetic Activity Research Telescope at Hida Observatory of Kyoto University. In the EUV images obtained by the Atmospheric Imaging Assembly on board the Solar Dynamic Observatory we found not only the corresponding EUV fast 'bright' coronal wave, but also the EUV fast 'faint' wave that is not associated with the H{alpha} Moreton wave. We also found a slow EUV wave, which corresponds to a typical EIT wave. Furthermore, we observed, for the first time, the oscillations of a prominence and a filament, simultaneously, both in the H{alpha} and EUV images. To trigger the oscillations by the flare-associated coronal disturbance, we expect a coronal wave as fast as the fast-mode MHD wave with the velocity of about 570-800 km s{sup -1}. These velocities are consistent with those of the observed Moreton wave and the EUV fast coronal wave.

Asai, Ayumi; Isobe, Hiroaki [Unit of Synergetic Studies for Space, Kyoto University, Yamashina, Kyoto 607-8471 (Japan); Ishii, Takako T.; Kitai, Reizaburo; Ichimoto, Kiyoshi; UeNo, Satoru; Nagata, Shin' ichi; Morita, Satoshi; Nishida, Keisuke; Shibata, Kazunari [Kwasan and Hida Observatories, Kyoto University, Yamashina, Kyoto 607-8471 (Japan); Shiota, Daikou [Advanced Science Institute, RIKEN, Wako, Saitama 351-0198 (Japan); Oi, Akihito [College of Science, Ibaraki University, Mito, Ibaraki 310-8512 (Japan); Akioka, Maki, E-mail: asai@kwasan.kyoto-u.ac.jp [Hiraiso Solar Observatory, National Institute of Information and Communications Technology, Hitachinaka, Ibaraki 311-1202 (Japan)

2012-02-15

 
 
 
 
101

Detection of H-alpha emission from z>3.5 submillimetre luminous galaxies with AKARI-FUHYU spectroscopy  

CERN Multimedia

We present tentative H-alpha emission line detections of four submillimetre-detected galaxies at z>3.5: the radio galaxies 8C1909+722 and 4C60.07 at signal-to-noise ratios (SNRs) of 3.1 and 2.5, and two submillimetre-selected galaxies (SMGs) near the first of these at SNRs of 10.0 and 2.4, made with the AKARI Space Telescope as part of the FUHYU mission program. These are the highest-redshift H-alpha detections in such galaxies, made possible by AKARI's unique near-infrared spectroscopic capability. The two radio galaxies had known redshifts and surrounding structure, and we have detected broad H-alpha components indicating the presence of dust-shrouded quasars. We conclude that powerful AGNs at z>3.5 occur in peaks of the star-formation density fields, supporting a close connection between stellar mass build-up and black hole mass assembly at this redshift. We also show that 4C60.07 is a binary AGN. The H-alpha detections of the two SMGs are the first redshift determinations for these sources, confirming the...

Sedgwick, Chris; Pearson, Chris; Smail, Ian; Im, Myungshin; Oyabu, Shinki; Takagi, Toshinobu; Matsuhara, Hideo; Wada, Takehiko; Lee, Hyung Mok; Jeong, Woong-Seob; White, Glenn J

2013-01-01

102

GH $\\alpha$ FaS : Galaxy H-alpha Fabry-Perot System for the WHT  

CERN Document Server

GH$\\alpha$FaS a new Fabry-Perot system, is now available at the William Herschel Telescope. It was mounted, for the first time, at the Nasmyth focus of the 4.2 meter WHT on La Palma in July 2007. Using modern technology, with a spectral resolution of the order R$\\sim$15000, and with a seeing limited spatial resolution, GH$\\alpha$FaS will provide a new look at the H$\\alpha$ -emitting gas over a 4.8 arcminutes circular field in the nearby universe. Many science programs can be done on a 4.2 metre class telescope in world class seeing conditions with a scanning Fabry-Perot. Not only galaxies but HII regions, planetary nebulae, supernova remnants and the diffuse interstellar medium are subjects for which unique data can be aquired rapidly. Astronomers from the Laboratoire d'Astrophysique Exp\\'erimentale (LAE) in Montr\\'eal, the Laboratoire d'Astrophysique de Marseille (LAM-OAMP), and the Instituto de Astrof\\'isica de Canarias (IAC), have inaugurated GH$\\alpha$FaS by studying in detail the dynamics of some nearby ...

Hernández, O; Carignan, C; Beckman, J; Gach, J L; Balard, P; Amram, P; Boulesteix, J; Corradi, R L M; de Denus-Baillargeon, M-M; Epinat, B; Relaño, M; Thibault, S; Vallée, P

2008-01-01

103

Pattern Speeds of Bars and Spiral Arms From H-alpha Velocity Fields  

CERN Document Server

We have applied the Tremaine-Weinberg method to 10 late-type barred spiral galaxies using data cubes, in H-alpha emission, from the GHAFAS and FANTOMM Fabry-Perot spectrometers. We have combined the derived bar (and/or spiral) pattern speeds with angular frequency plots to measure the corotation radii for the bars in these galaxies. We base our results on a combination of this method with a morphological analysis designed to estimate the corotation radius to bar-length ratio using two independent techniques on archival near infrared images, and although we are aware of the limitation of the application of the Tremaine-Weinberg method using ionised gas observations, we find consistently excellent agreement between bar and spiral arm parameters derived using different methods. In general, the corotation radius, measured using the Tremaine-Weinberg method, is closely related to the bar length, measured independently from photometry and consistent with previous studies. Our corotation/bar-length ratios and patter...

Fathi, Kambiz; Piñol-Ferrer, Nuria; Hernandez, Olivier; Martinez-Valpuesta, Inma; Carignan, Claude

2009-01-01

104

The Tremaine-Weinberg method for pattern speeds using H-alpha emission from ionized gas  

CERN Multimedia

The Fabry-Perot interferometer FaNTOmM was used at the 3.6m Canada France Hawaii Telescope and the 1.6m Mont Megantic Telescope to obtain data cubes in H-alpha of 9 nearby spiral galaxies from which maps in integrated intensity, velocity, and velocity dispersion were derived. We then applied the Tremaine-Weinberg method, in which the pattern speed can be deduced from its velocity field, by finding the integrated value of the mean velocity along a slit parallel to the major axis weighted by the intensity and divided by the weighted mean distance of the velocity points from the tangent point measured along the slit. The measured variables can be used either to make separate calculations of the pattern speed and derive a mean, or in a plot of one against the other for all the points on all slits, from which a best fit value can be derived. Linear fits were found for all the galaxies in the sample. For two galaxies a clearly separate inner pattern speed with a higher value, was also identified and measured.

Beckman, John E; Piñol, Núria; Toonen, Silvia; Hernandez, Olivier; Carignan, Claude

2007-01-01

105

H-alpha Kinematics of the SINGS Nearby Galaxies Survey. II  

CERN Document Server

This is the second part of an H-alpha kinematics follow-up survey of the Spitzer Infrared Nearby Galaxies Survey (SINGS) sample. The aim of this program is to shed new light on the role of baryons and their kinematics and on the dark/luminous matter relation in the star forming regions of galaxies, in relation with studies at other wavelengths. The data for 37 galaxies are presented. The observations were made using Fabry-Perot interferometry with the photon-counting camera FaNTOmM on 4 different telescopes, namely the Canada-France-Hawaii 3.6m, the ESO La Silla 3.6m, the William Herschel 4.2m, and the Observatoire du mont Megantic 1.6m telescopes. The velocity fields are computed using custom IDL routines designed for an optimal use of the data. The kinematical parameters and rotation curves are derived using the GIPSY software. It is shown that non-circular motions associated with galactic bars affect the kinematical parameters fitting and the velocity gradient of the rotation curves. This leads to incorrec...

Dicaire, I; Amram, P; Hernández, O; Chemin, L; Daigle, O; de Denus-Baillargeon, M -M; Balkowski, C; Boselli, A; Fathi, K; Kennicutt, R C

2008-01-01

106

Proper Motions of H-alpha filaments in the Supernova Remnant RCW 86  

CERN Multimedia

We present a proper motion study of the eastern shock-region of the supernova remnant RCW 86 (MSH 14-63, G315.4-2.3), based on optical observations carried out with VLT/FORS2 in 2007 and 2010. For both the northeastern and southeastern regions, we measure an average proper motion of H-alpha filaments of 0.10 +/- 0.02 arcsec/yr, corresponding to 1200 +/- 200 km/s at 2.5kpc. There is substantial variation in the derived proper motions, indicating shock velocities ranging from just below 700 km/s to above 2200 km/s. The optical proper motion is lower than the previously measured X-ray proper motion of northeastern region. The new measurements are consistent with the previously measured proton temperature of 2.3 +/- 0.3 keV, assuming no cosmic-ray acceleration. However, within the uncertainties, moderately efficient (< 27 per cent) shock acceleration is still possible. The combination of optical proper motion and proton temperature rule out the possibility that RCW 86 has a distance less than 1.5kpc. The simil...

Helder, E A; Bamba, A; Bleeker, J A M; Burrows, D N; Ghavamian, P; Yamazaki, R

2013-01-01

107

The KPNO International Spectroscopic Survey. V. H-alpha-selected Survey List 3  

CERN Document Server

The KPNO International Spectroscopic Survey (KISS) is an objective-prism survey designed to detect extragalactic emission-line objects. It combines many of the features of previous slitless spectroscopic surveys with the advantages of modern CCD detectors, and is the first purely digital objective-prism survey for emission-line galaxies (ELGs). Here we present the third list of ELG candidates selected from our red spectral data, which cover the wavelength range 6400 to 7200 A. In most cases, the detected emission line is H-alpha. The current survey list covers the region of the NOAO Deep Wide-Field Survey (NDWFS). This survey covers two fields; the first is 3 x 3 degrees square and located at RA = 14h 30m, DEC = 34.5 deg (B1950), the second is 2.3 x 4.0 degrees and centered at RA = 2h 7.5m, DEC = -4.75 deg. A total area of 19.65 deg^2 is covered by the KISS data. A total of 261 candidate emission-line objects have been selected for inclusion in the survey list (13.3 per deg^2). We tabulate accurate coordinate...

Jangren, A; Sarajedini, V L; Gronwall, C; Werk, J K; Chomiuk, L; Moody, J W; Boroson, T A; Jangren, Anna; Salzer, John J.; Sarajedini, Vicki L.; Gronwall, Caryl; Werk, Jessica K.; Chomiuk, Laura; Boroson, Todd A.

2005-01-01

108

Analysis of EUV, UV, and H-alpha Emission from Two Very Different Prominences  

Science.gov (United States)

Analysis of EUV, UV, and H-alpha Emission from Two Very Different Prominences T. Kucera (NASA/GSFC), E. Landi (Artep Inc.) We analyze the properties of a pair of prominences observed the UV and EUV in April 2004. One was a generally quiet prominence which exhibited a period of activation. Another was a large "coronal cloud" type prominence. Both were observed in by SOHO/SUMER, TRACE, and in H? by BBSO and MLSO. The quiet promince was also observed by the SOHO/CDS instrument. TRACE and H? data provide 2D images on with time cadences on the order of 1 minute. The SUMER data was taken from a single slit location with a 90 second cadence and included a number of lines spanning the temperature range 80,000 to 1.6 million K. This observing program was designed to allow us to study prominence dynamics. CDS raster data was taken with a slower cadence, in lines formed at temperatures from 20,000 - 1 million K. We combine these different data sets to analyze the thermal properties, including differential emission measures (DEMs), of these very different prominences, and compare the results to those of prominences previously analyzed by ourselves and others. This work was partly funded through a NASA Heliophysics GI RTOP and NASA award NNH04AA12

Kucera, T. A.; Landi, E.

2008-05-01

109

Star formation properties in the Local Volume galaxies via $H\\alpha$ and FUV fluxes  

CERN Document Server

A distance-limited sample of 869 objects from the Updated Nearby Galaxy Catalog is used to characterize the star formation status of the Local Volume population. We present a compiled list of 1217 star formation rate (SFR) estimates for 802 galaxies within 11 Mpc from us, derived from the H-alpha imaging surveys and GALEX far-ultraviolet survey. We briefly discuss some basic scaling relations between SFR and luminosity, morphology, HI-mass, surface brightness, as well as environment of the galaxies. About 3/4 of our sample consist of dwarf galaxies, for which we offer a more refined classification. We note that the specific star formation rate of nearly all luminous and dwarf galaxies does not exceed the maximum value: $\\log(SFR/L_K) = -9.4$ [yr$^{-1}$]. The bulk of spiral and blue dwarf galaxies have enough time to generate their stellar mass during the cosmological time, $T_0$, with the observed SFRs. They dispose of a sufficient amount of gas to support their present SFRs over the next $T_0$ term. We note ...

Karachentsev, Igor D

2013-01-01

110

Free-space quantum cryptography in the H-alpha Fraunhofer window  

Science.gov (United States)

Free-space Quantum key distribution (QKD) has shown the potential for the practical production of cryptographic key for ultra-secure communications. The performance of any QKD system is ultimately limited by the signal to noise ratio on the single-photon channel, and over most useful communications links the resulting key rates are impractical for performing continuous one-time-pad encryption of today's broadband communications. We have adapted clock and data recovery techniques from modern telecommunications practice, combined with a synchronous classical free-space optical communications link operating in parallel, to increase the repetition rate of a free-space QKD system by roughly 2 orders of magnitude over previous demonstrations. We have also designed the system to operate in the H-alpha Fraunhofer window at 656.28 nm, where the solar background is reduced by roughly 7 dB. This system takes advantage of high efficiency silicon single-photon avalanche photodiodes with <50ps timing resolution that are expected to enable operation at a repetition rate of 2.5 GHz. We have identified scalable solutions for delivering sustained one-time-pad encryption at 10 Mbps, thus making it possible to integrate quantum cryptography into first-generation Ethernet protocols.

Rogers, D. J.; Bienfang, J. C.; Mink, A.; Hershman, B. J.; Nakassis, A.; Tang, X.; Ma, L.; Su, D. H.; Williams, Carl J.; Clark, Charles W.

2006-09-01

111

Decomposition width - a new width parameter for matroids  

CERN Document Server

We introduce a new width parameter for matroids called decomposition width and prove that every matroid property expressible in the monadic second order logic can be computed in linear time for matroids with bounded decomposition width if their decomposition is given. Since decompositions of small width for our new notion can be computed in polynomial time for matroids of bounded branch-width represented over finite fields, our results include recent algorithmic results of Hlineny [J. Combin. Theory Ser. B 96 (2006), 325-351] in this area and extend his results to matroids not necessarily representable over finite fields.

Kral, Daniel

2009-01-01

112

The broad H-alpha, [O III] line wings in stellar supercluster A of NGC2363 and the turbulent mixing layer hypothesis  

CERN Document Server

Context. SuperclusterA in the extragalactic HII region NGC2363 is remarkable for the hypersonic gas seen as faint extended broad emission lines with a full width zero intensity of 7000km/s. Aims. We explore the possibility that the observed broad profiles are the result of the interaction of a high velocity cluster wind with dense photoionized clumps. Methods. The geometry considered is that of near static photoionized condensations at the surface of which turbulent mixing layers arise as a result of the interaction with the hot wind. The approximative treatment of turbulence is carried out using the mixing length approach of Canto & Raga. The code mappings Ic is used to derive the mean quantities describing the flow and to compute the line emissivities within the turbulent layers. The velocity projection in three dimensions of the line sources is carried out analytically. Results. A fast entraining wind of up to ~4300km/s appears to be required to reproduce the faint wings of the broad H-alpha and [O III...

Binette, Luc; Ubeda, Leonardo; Raga, Alejandro C; Robert, Carmelle; Krongold, Yair

2009-01-01

113

Investigation of the Differential Rotation by H-Alpha Filaments and Long-Lived Magnetic Features for Solar Activity Cycles 20 and 21  

CERN Document Server

For solar activity cycles 20 and 21 (1966-1985) the solar differential rotation has been investigated using H{\\alpha} filaments and relatively small-scale long-lived magnetic features with negative and positive polarities. We used annual averaged angular velocities of quiescent H{\\alpha} filaments from H{\\alpha} photoheliograms of the Abastumani Astrophysical Observatory film collection and selected long-lived magnetic features from the McIntosh atlas (McIntosh, Willock, and Thompson, Atlas of Stackplots, NGDC, 1991). We have determined coefficients of Faye's formulas for H{\\alpha} filaments as well as for long-lived magnetic features and have found that for solar cycles 20 and 21 the H{\\alpha} filaments have lower rotation rates and rotated more differentially than the long-lived magnetic features.

Gigolashvili, M Sh; Kukhianidze, V J

2012-01-01

114

High specific activity N-Acetyl-3{sup H}-{alpha}-Aspartyl- L-Glutamic at micro mole scale; Sintesis de N-Acetil-3{sup H}- {alpha} -Aspartil-Glutamico a escala de Micromoles  

Energy Technology Data Exchange (ETDEWEB)

High specific activity N-Acetyl-3{sup H}- {alpha} -Aspartyl-I-Glutamic acid at micro mole scale in prepared acetylating L- {alpha} -Aspartyl-L-glutamic with 3{sup H}-acetic anhydride in re distilled toluene. The product le purified through cationic and anionic columns. The radiochemical purity as determined by thin-layer chromatography is greater then 99% at the time preparation. (Author) 5 refs.

Suarez, C.

1984-07-01

115

Stellar Populations and the Star Formation Histories of LSB Galaxies: I. Optical and H-alpha Imaging  

CERN Document Server

This paper presents optical and H-alpha imaging for a large sample of LSB galaxies selected from the PSS-II catalogs (Schombert et. al 1992). As noted in previous work, LSB galaxies span a range of luminosities (-10 > M_V > -20) and sizes (0.3 kpc < R_V25 < 10 kpc), although they are consistent in their irregular morphology. Their H-alpha luminosities (L(H-alpha) range from 10^36 to 10^41 ergs s^-1 (corresponding to a range in star formation, using canonical prescriptions, from 10^-5 to 1 M_solar yr^-1). Although their optical colors are at the extreme blue edge for galaxies, they are similar to the colors of dwarf galaxies (van Zee 2001) and gas-rich irregulars (Hunter & Elmegreen 2006). However, their star formation rates per unit stellar mass are a factor of ten less than other galaxies of the same baryonic mass, indicating that they are not simply quiescent versions of more active star forming galaxies. This paper presents the data, reduction techniques and new philosophy of data storage and pre...

Schombert, James; McGaugh, Stacy

2011-01-01

116

HIGH RESOLUTION H{alpha} IMAGES OF THE BINARY LOW-MASS PROPLYD LV 1 WITH THE MAGELLAN AO SYSTEM  

Energy Technology Data Exchange (ETDEWEB)

We utilize the new Magellan adaptive optics system (MagAO) to image the binary proplyd LV 1 in the Orion Trapezium at H{alpha}. This is among the first AO results in visible wavelengths. The H{alpha} image clearly shows the ionization fronts, the interproplyd shell, and the cometary tails. Our astrometric measurements find no significant relative motion between components over {approx}18 yr, implying that LV 1 is a low-mass system. We also analyze Large Binocular Telescope AO observations, and find a point source which may be the embedded protostar's photosphere in the continuum. Converting the H magnitudes to mass, we show that the LV 1 binary may consist of one very-low-mass star with a likely brown dwarf secondary, or even plausibly a double brown dwarf. Finally, the magnetopause of the minor proplyd is estimated to have a radius of 110 AU, consistent with the location of the bow shock seen in H{alpha}.

Wu, Y.-L.; Close, L. M.; Males, J. R.; Follette, K.; Morzinski, K.; Kopon, D.; Rodigas, T. J.; Hinz, P. [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Puglisi, A.; Esposito, S.; Pinna, E.; Riccardi, A.; Xompero, M.; Briguglio, R., E-mail: yalinwu@email.arizona.edu [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze (Italy)

2013-09-01

117

Evidence of Environmental Dependencies of Type Ia Supernovae from the Nearby Supernova Factory indicated by Local H{\\alpha}  

CERN Document Server

(Abridged) We study the host galaxy regions in close proximity to Type Ia supernovae (SNe Ia) to analyze relations between the properties of SN Ia events and environments most similar to where their progenitors formed. We focus on local H\\alpha\\ emission as an indicator of young environments. The Nearby Supernova Factory has obtained flux-calibrated spectral timeseries for SNe Ia using integral field spectroscopy, allowing the simultaneous measurement of the SN and its immediate vicinity. For 89 SNe Ia we measure H\\alpha\\ emission tracing ongoing star formation within a 1 kpc radius around each SN. This constitutes the first direct study of the local environment for a large sample of SNe Ia also having accurate luminosity, color and stretch measurements. We find that SNe Ia with local H\\alpha\\ emission are redder by 0.036+/-0.017 mag, and that the previously-noted correlation between stretch and host mass is entirely driven by the SNe Ia coming from passive regions. Most importantly, the mean standardized bri...

Rigault, M; Aldering, G; Antilogus, P; Aragon, C; Bailey, S; Baltay, C; Bongard, S; Buton, C; Canto, A; Cellier-Holzem, F; Childress, M; Chotard, N; Fakhouri, H K; Feindt, U; Fleury, M; Gangler, E; Greskovic, P; Guy, J; Kim, A G; Kowalski, M; Lombardo, S; Nordin, J; Nugent, P; Pain, R; Pécontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Runge, K; Saunders, C; Scalzo, R; Smadja, G; Tao, C; Thomas, R C; Weaver, B A

2013-01-01

118

Disparity between H\\alpha\\ and H\\beta\\ in SN 2008in: inhomogeneous external layers of type IIP supernovae?  

CERN Multimedia

We study disparity between H\\alpha\\ and H\\beta\\ in early spectra of the type IIP supernova SN 2008in. The point is that these lines cannot be described simultaneously in a spherically-symmetric model with the smooth density distribution. It is shown that an assumption of a clumpy structure of external layers of the envelope resolves the problem. We obtain estimates of the velocity at the inner border of the inhomogeneous zone (\\approx6100 km s^{-1}), the filing factor of inhomogeneities (\\leq0.5), and the mass of the inhomogeneous layers (~ 0.03 M_{\\odot}). The amplitude of flux fluctuations in the early spectrum of H\\alpha\\ (\\Delta F/F ~ 10^{-2}) imposes a constraint on the size of inhomogeneities (\\leq 200 km s^{-1}). A detection of fluctuations in the early H\\alpha\\ of type IIP supernovae might become an observational test of the inhomogeneous structure of their envelopes. We propose also the indirect test of the clumpy structure of external layers: the study of properties of the initial radiation outburst...

Chugai, N N

2013-01-01

119

Cosmic Star Formation Activity at z=2.2 Probed by H-alpha Emission Line Galaxies  

CERN Document Server

We present a pilot narrow-band survey of H-alpha emitters at z=2.2 in the Great Observatories Origins Deep Survey North (GOODS-N) field with MOIRCS instrument on the Subaru telescope. The survey reached a 3 sigma limiting magnitude of 23.6 (NB209) which corresponds to a 3 sigma limiting line flux of 2.5 x 10^-17 erg s^-1 cm^-2 over a 56 arcmnin^2 contiguous area (excluding a shallower area). From this survey, we have identified 11 H-alpha emitters and one AGN at z=2.2 on the basis of narrow-band excesses and photometric redshifts. We obtained spectra for seven new objects among them, including one AGN, and an emission line above 3 sigma is detected from all of them. We have estimated star formation rates (SFR) and stellar masses (M_star) for individual galaxies. The average SFR and M_star is 27.8M_solar yr^-1 and 4.0 x 10^10M_solar, respectivly. Their specific star formation rates are inversely correlated with their stellar masses. Fitting to a Schechter function yields the H-alpha luminosity function with lo...

Tadaki, Ken-ichi; Koyama, Yusei; Hayashi, Masao; Tanaka, Ichi; Tokoku, Chihiro

2010-01-01

120

Large-scale wind structures in OB supergiants: a search for rotationally modulated H\\alpha variability  

CERN Multimedia

We present the results of a long-term monitoring campaign of the H\\alpha line in a sample of bright OB-supergiants (O7.5-B9) that aims at detecting rotationally modulated changes potentially related to the existence of large-scale wind structures. A total of 22 objects were monitor ed during 36 nights spread over 6 months in 2001-2002. Coordinated broad-band photometric observations were also obtained for some targets. Conspicuous evidence for variability in H\\alpha is found for the stars displaying a feature contaminated by wind emission. Most changes take place on a daily time-scale, although hourly variations are also occasionally detected. Convincing evidence for a cyclical pattern of variability in H\\alpha has been found in 2 stars: HD 14134 and HD 42087 (periodic signals are also detected in other stars, but independent confirmation is required). Rotational modulation is suggested from the similarity between the observed recurrence time-scales (in the range 13-25 days) and estimated periods of stellar r...

Morel, T; Pati, A K; Kuppuswamy, K; Carini, M T; Wood, E; Zimmerman, R

2004-01-01

 
 
 
 
121

Sub-THz and H{\\alpha} activity during the preflare and main phases of a GOES class M2 event  

CERN Document Server

Radio and optical observations of the evolution of flare-associated phenomena have shown an initial and rapid burst at 0.4 THz only followed subsequently by a localized chromospheric heating producing an H{\\alpha} brightening with later heating of the whole active region. A major instability occurred several minutes later producing one impulsive burst at microwaves only, associated with an M2.0 GOES X-ray flare that exhibited the main H{\\alpha} brightening at the same site as the first flash. The possible association between long-enduring time profiles at soft X-rays, microwaves, H{\\alpha} and sub-THz wavelengths is discussed. In the decay phase the H{\\alpha} movie shows a disrupting magnetic arch structure ejecting dark, presumably chromospheric, material upwards. The time sequence of events suggests genuine interdependent and possibly non-thermal instabilities triggering phenomena, with concurrent active region plasma heating and material ejection.

Kaufmann, Pierre; de Castro, C Guillermo Giménez; White, Stephen M; Raulin, Jean-Pierre; Correia, Emilia; Fernandes, Luis Olavo; de Souza, Rodney V; Godoy, Rodolfo; Marun, Adolfo; Pereyra, Pablo

2011-01-01

122

Scattering polarization and the Hanle effect in H-alpha as a probe of chromospheric magnetism: Modeling vs. Observations  

CERN Multimedia

The Hanle effect in strong spectral lines is the physical mechanism that should be increasingly exploited for quantitative explorations of the magnetism of the quiet solar chromospheric plasma. Here we show, by means of multilevel radiative transfer calculations and new spectropolarimetric observations, that the amplitude and shape of the scattering polarization profiles of the H-alpha line is very sensitive to the strength and structure of the chromospheric magnetic field. The interpretation of the observations in terms of one-dimensional radiative transfer modeling suggests that there is an abrupt magnetization in the upper chromosphere of the quiet Sun.

Stepan, Jiri; Ramelli, Renzo; Bianda, Michele

2011-01-01

123

Distribution of neutron resonance widths  

CERN Document Server

Recent data on neutron resonance widths indicate disagreement with the Porter-Thomas distribution (PTD). I discuss the theoretical arguments for the PTD, possible theoretical modifications, and I summarize the experimantal evidence.

Weidenmueller, Hans A

2011-01-01

124

H{\\alpha} and UV luminosities and star formation rates in a large sample of luminous compact galaxies  

CERN Multimedia

We present the results of a statistical study of the star formation rates (SFR) derived from the Galaxy Evolution Explorer (GALEX) observations in the ultraviolet continuum and in the H\\alpha emission line for a sample of about 800 luminous compact galaxies (LCGs). Galaxies in this sample have a compact structure and include one or several regions of active star formation. Global galaxy characteristics (metallicity, luminosity, stellar mass) are intermediate between ones of the nearby blue compact dwarf (BCD) galaxies and Lyman-break galaxies (LBGs) at high redshifts z > 2 - 3. SFRs were corrected for interstellar extinction which was derived from the optical Sloan Digital Sky Survey (SDSS) spectra. We find that SFRs derived from the galaxy luminosities in the far ultraviolet (FUV) and near ultraviolet (NUV) ranges vary in a wide range from 0.18 M_Sun/yr to 113 M_Sun/yr with median values of 3.8 M_Sun/yr and 5.2 M_Sun/yr, respectively. Simple regression relations are found for luminosities L(H\\alpha) and L(UV...

Parnovsky, S L; Izotov, Y I

2012-01-01

125

The H-alpha luminosity function at redshift 2.2: A new determination using VLT/HAWK-I  

CERN Document Server

We aim to place new, strengthened constraints on the luminosity function (LF) of H-alpha emitting galaxies at redshift z=2.2, and to further constrain the instantaneous star-formation rate density of the universe (rho*). We have used the new HAWK-I instrument at ESO-VLT to obtain extremely deep narrow-band (line; NB2090) and broad-band (continuum; Ks) imaging observations. The target field is in the GOODS-South, providing us with a rich multi-wavelength auxiliary data set, which we utilise for redshift confirmation and to estimate dust content. We use this new data to measure the faint-end slope (alpha) of LF(H-alpha) with unprecedented precision. The data are well fit by a Schechter function and also a single power-law, yielding alpha=(-1.72 +/- 0.20) and (-1.77 +/- 0.21), respectively. Thus we are able to confirm the steepening of alpha from low- to high-z predicted by a number of authors and observed at other wavelengths. We combine our LF data-points with those from a much shallower but wider survey at z=...

Hayes, Matthew; Ostlin, Goran

2009-01-01

126

Photometric H alpha and [O II] Luminosity Function of SDF and SXDF Galaxies: Implications for Future Baryon Oscillation Surveys  

CERN Multimedia

Efficient selection of emission line galaxies at z > 1 by photometric information in wide field surveys is one of the keys for future spectroscopic surveys to constrain dark energy using the baryon acoustic oscillation (BAO) signature. Here we estimate the H alpha and [O II] line luminosity functions of galaxies at z = 0.5-1.7 using a novel approach where multi-wavelength imaging data is used to jointly estimate both photometric redshifts and star-formation rates. These photometric estimates of line luminosities at high-redshift use the large data sets of the Subaru Deep Field and Subaru XMM-Newton Deep Field (covering \\sim 1 deg^2) and are calibrated with the spectroscopic data of the local Sloan Digital Sky Survey galaxies. The derived luminosity functions (especially H alpha) are in reasonable agreement with the past estimates based on spectroscopic or narrow-band-filter surveys. This dataset is useful for examining the photometric selection of target galaxies for BAO surveys because of the large cosmologi...

Sumiyoshi, Masanao; Oshige, Shunsuke; Glazebrook, Karl; Akiyama, Masayuki; Morokuma, Tomoki; Motohara, Kentaro; Shimasaku, Kazuhiro; Hayashi, Masao; Yoshida, Makiko; Kashikawa, Nobunari; Kodama, Tadayuki

2009-01-01

127

Initial Data Release from the INT Photometric H-alpha Survey of the Northern Galactic Plane (IPHAS)  

CERN Document Server

The INT/WFC Photometric H-alpha Survey of the Northern Galactic Plane (IPHAS) is an imaging survey being carried out in H-alpha, r' and i' filters, with the Wide Field Camera (WFC) on the 2.5-metre Isaac Newton Telescope (INT) to a depth of r'=20 (10 sigma). The survey is aimed at revealing large scale structure in our local galaxy, and also the properties of key early and late populations making up the Milky Way. Mapping emission line objects enables a particular focus on objects in the young and old stages of stellar evolution ranging from early T-Tauri stars to late planetary nebulae. In this paper we present the IPHAS Initial Data Release, primarily a photometric catalogue of about 200 million unique objects, coupled with associated image data covering about 1600 square degrees in three passbands. We note how access to the primary data products has been implemented through use of standard virtual observatory publishing interfaces. Simple traditional web access is provided to the main IPHAS photometric cat...

González-Solares, E A; Greimel, R; Drew, J E; Irwin, M J; Sale, S E; Andrews, K; Aungwerojwit, A; Barlow, M J; Besselaar, E van den; Corradi, R L M; Gänsicke, B T; Groot, P J; Hales, A S; Hopewell, E C; Hu, H; Irwin, J; Knigge, C; Lagadec, E; Leisy, P; Lewis, J R; Mampaso, A; Matsuura, M; Moont, B; Morales-Rueda, L; Morris, R A H; Naylor, T; Parker, Q A; Prema, P; Pyrzas, S; Rixon, G T; Rodríguez-Gil, P; Roelofs, G; Sabin, L; Skillen, I; Suso, J; Tata, R; Viironen, K; Vink, J S; Witham, A; Wright, N J; Zijlstra, A A; Zurita, A; Drake, J; Fabregat, J; Lennon, D J; Lucas, P W; Martín, E L; Steeghs, D; Unruh, Y C

2007-01-01

128

Autoradiography of sup 3 H-. alpha. -fluoromethyl histidine in mice; Correlation with the kidney histidine decarboxylase activity  

Energy Technology Data Exchange (ETDEWEB)

Tritium-{alpha}-fluoromethyl histidine ({sup 3}H-{alpha}-FMH), designed as a K{sub cat}-inhibitor of mammalian histidine decarboxylase (EC 4.1.1.22), was administered intravenously in male and pregnant female mice of the NMRI strain and the distribution of tritium in the body recorded by whole-body and microautoradiography. The results showed penetration of radioactivity into most tissues within 5 min. after the injection. After 4 hrs the highest levels of radioactivity were present in the intestinal content and in the kidneys. In the pregnant animal there was also a high labelling of the foetal tissues. When whole-body sections were washed in TCA prior to the autoradiographic exposure to retain only protein-bound radioactivity, a distinct labelling pattern was seen in the kidneys of the pregnant female mice ebut not in those of the male mice. Microautoradiography of the kidneys showed that the cells involved were located within the proximal convoluted tubuli. In several mouse strains, including the NMRI, the activity of kidney histidine decarboxylase is low in the males but high in females during a transient period of pregnancy. Incorporation of tritium into kidney protein after treatment with {sup 3}H-{alpha}-FMH, was correlated to a loss in histidine decarboxylase activity. The isotopic labelling was confined mainly to a component which cofractionated with histidine decarboxylase in polyacrylamidegel electrophoresis (PAGE) under nondenaturing conditions. Our data indicate that the cells described above represent the location of kidney histidine decarboxylase. (author).

Hammar, L. (Department of Veterinary Virology, Biomedical Center, Uppsala (Sweden)); Henningsson, S. (Division of Clinical Pharmacology, University Hospital, Uppsala (Sweden)); Henningsson, A.-C. (Department of Obstetrics and Gynaecology, Univ. Hospital, Uppsala (Sweden)); Appelgreen, L.-E.; Tjaelve, H. (Department of Pharmacology and Toxicology, Biomedical Center, Uppsala (Sweden)); Kollonitsch, J. (Merck, Sharp and Dohme Research Laboratories, Rahway, New Jersey (USA))

1990-01-01

129

SBS 0335-052 E and W: implications of new broad-band and H-alpha photometry  

CERN Multimedia

We present the results of deep multicolour CCD imaging with the 6-m telescope of the pair of extremely metal-deficient gas-rich dwarf galaxies SBS 0335-052 E and W. The total magnitudes in U,B,V,R,I bands and the integrated fluxes of H-alpha emission are measured for both galaxies, and their integrated colours are derived. The analysis of their surface brightness (SB) distributions is performed with the use of the azimuthally-averaged SB profiles. The latter were modeled by the central Gaussian component and the underlying exponential `disk', mainly contributing in the outermost, very low SB regions. The colours of these LSB components are used to estimate the age of the oldest visible stellar population. For the interpretation of the observed LSB colours their contamination by the nebular emission of ionized gas is accounted for by the use of the distribution of H-alpha flux. We compare the derived `gas-free' colours with the colours predicted by the evolution synthesis models from the PEGASE.2 package, cons...

Pustilnik, S A; Kniazev, A Yu

2004-01-01

130

An Equivalent Gauge and the Equivalence Theorem  

CERN Document Server

I describe a novel covariant formulation of massive gauge theories in which the longitudinal polarization vectors do not grow with the energy. Therefore in the present formalism, differently from the ordinary one, the energy and coupling power-counting is completely transparent at the level of individual Feynman diagrams, with obvious advantages both at the conceptual and practical level. Since power-counting is transparent, the high-energy limit of the amplitudes involving longitudinal particles is immediately taken, and the Equivalence Theorem is easily demonstrated at all orders in perturbation theory. Since the formalism makes the Equivalence Theorem self-evident, and because it is based on a suitable choice of the gauge, we can call it an "Equivalent Gauge".

Wulzer, Andrea

2013-01-01

131

A star-bursting proto-cluster in making associated to a radio galaxy at z=2.53 discovered by H_alpha imaging  

CERN Document Server

We report a discovery of a proto-cluster in vigorous assembly and hosting strong star forming activities, associated to a radio galaxy USS 1558-003 at z=2.53, as traced by a wide-field narrow-band H_alpha imaging with MOIRCS on Subaru Telescope. We find 68 H_alpha emitters with dust-uncorrected SFRs down to 8.6 Msun/yr. Their spatial distribution indicates that there are three prominent clumps of H_alpha emitters, one surrounding the radio galaxy and another located at ~1.5 Mpc away to the south-west, and the other located in between the two. These contiguous three systems are very likely to merge together in the near future and may grow to a single more massive cluster at later times. Whilst most H_alpha emitters reside in the "blue cloud" on the color--magnitude diagram, some emitters have very red colors with J-Ks>1.38(AB). Interestingly, such red H_alpha emitters are located towards the faint end of the red sequence, and they tend to be located in the high density clumps. We do not see any statistically s...

Hayashi, Masao; Tadaki, Ken-ichi; Koyama, Yusei; Tanaka, Ichi

2012-01-01

132

H-alpha solar flare activity in Bou 2030 and 2032, SERF interval, October 6-8, 1979  

International Nuclear Information System (INIS)

During the SERF interval of the SMY, October 4 to 9, 1979, the observations of regions Bou 2030 and 2032 were coordinated. An analysis of H-alpha observations indicates that, contrary to expectations, flares initiated in the magnetically simpler sunspot group Bou 2030 (Hale 16 341) occurred north off Bou 2032. The enhanced occurrence of flares in Bou 2030 on October 6, 1979 was located in an area with pronounced changes in polarity and structure of the background field in the neighbourhood of Bou 2030. The new positive large-scale field interacted with the negative field of the following spot B. Emission flare structures developed homologously along the new neutral line of the large-scale field. In analysing the pre-flare situation in a particular active region, it is therefore also necessary to know the characteristics of the large-scale field. (author).

2030-01-00

133

Equivalent Fraction Pointer  

Science.gov (United States)

This interactive Java applet helps users explore equivalent fractions through partitioning circles and squares. The applet provides a random fraction and the user creates one or two equivalent representations of that fraction by partitioning and coloring a square (or circle). The applet also plots the fraction on a number line and points from the shape to the number line displaying its equivalent value while the fraction is being built. Options include choice of circles or squares, one or two equivalent fractions, and a scoring feature allows users to keep track of the number correct.

2006-01-01

134

Equivalent Fraction Finder  

Science.gov (United States)

This interactive Java applet helps users explore equivalent fractions through partitioning circles and squares. The applet provides a random fraction and the user creates one or two equivalent representations of that fraction by partitioning and coloring a square (or circle). The applet also plots the fraction on a number line and points from the shape to the number line displaying its equivalent value after the fraction is built. Options include choice of circles or squares, one or two equivalent fractions, and a scoring feature allows users to keep track of the number correct.

2006-01-01

135

Detection of an H-alpha Emission Line on a Quasar, RX J1759.4+6638, at z=4.3 with AKARI  

CERN Multimedia

We report the detection of an H-alpha emission line in the low resolution spectrum of a quasar, RX J1759.4+6638, at a redshift of 4.3 with the InfraRed Camera (IRC) onboard the AKARI. This is the first spectroscopic detection of an H-alpha emission line in a quasar beyond z=4. The overall spectral energy distribution (SED) of RX J1759.4+6638 in the near- and mid-infrared wavelengths agrees with a median SED of the nearby quasars and the flux ratio of F(Ly-alpha)/F(H-alpha) is consistent with those of previous reports for lower-redshift quasars.

Oyabu, Shinki; Ohyama, Youichi; Matsuhara, Hideo; Takagi, Toshinobu; Nakagawa, Takao; Onaka, Takashi; Fujishiro, Naofumi; Ishihara, Daisuke; Ita, Yoshifusa; Kataza, Hirokazu; Kim, Woojung; Matsumoto, Toshio; Murakami, Hiroshi; Sakon, Itsuki; Tanabe, Toshihiko; Uemizu, Kazunori; Ueno, Munetaka; Usui, Fumihiko; Watarai, Hidenori; Haze, Kanae

2007-01-01

136

Widths of isovector monopole resonances  

International Nuclear Information System (INIS)

The widths of the isovector monopole ?Tsub(z) = 1 component in 208Tl, 140La, 120In and 90Y are evaluated within the self-consistent Hartree-Fock + charge-exchange RPA using the Skyrme interaction. The coupling of 1p-1h states to 2p-2h configurations is microscopically calculated. The results are compared with those of recent pion charge-exchange reactions. (author).

1983-01-01

137

?(1520) ? ?? Radiative-Decay Width  

International Nuclear Information System (INIS)

The radiative decay ?(1520) ? ?? was recorded in the exclusive reaction p + N ? ?(1520)K+ + N at the SPHINX facility. The branching ratio for this decay and the corresponding partial width were found to be, respectively, Br[?(1520) ? ??] = (1.02 ± 0.21) x 10-2 and ?[?(1520) ? ??] = 159 ± 35 keV (the quoted errors are purely statistical, the systematic errors being within 15%).

2005-01-01

138

Width of laminar laboratory rivers.  

UK PubMed Central (United Kingdom)

A viscous fluid flowing over plastic grains spontaneously generates single-thread channels. With time, these laminar analogues of alluvial rivers reach a reproducible steady state, showing a well-defined width and cross section. In the absence of sediment transport, their shape conforms with the threshold hypothesis which states that, at equilibrium, the combined effects of gravity and flow-induced stress maintain the bed surface at the threshold of motion. This theory explains how the channel selects its size and slope for a given discharge. In this light, laboratory rivers illustrate the similarity between the avalanche angle of granular materials and Shields's criterion for sediment transport.

Seizilles G; Devauchelle O; Lajeunesse E; Métivier F

2013-05-01

139

Spreading Widths of Doorway States  

CERN Multimedia

As a function of energy E, the average strength function S(E) of a doorway state is commonly assumed to be Lorentzian in shape and characterized by two parameters, the peak energy E_0 and the spreading width Gamma. The simple picture is modified when the density of background states that couple to the doorway state changes significantly in an energy interval of size Gamma. For that case we derive an approximate analytical expression for S(E). We test our result successfully against numerical simulations. Our result may have important implications for shell--model calculations.

De Pace, A; Weidenmueller, H A

2010-01-01

140

The Wyoming Survey for H-alpha. III. A Multi-wavelength Look at Attenuation by Dust in Galaxies out to z~0.4  

CERN Document Server

We report results from the Wyoming Survey for H-alpha (WySH), a comprehensive four-square degree survey to probe the evolution of star-forming galaxies over the latter half of the age of the Universe. We have supplemented the H-alpha data from WySH with infrared data from the Spitzer Wide-area Infrared Extragalactic (SWIRE) Survey and ultraviolet data from the Galaxy Evolution Explorer (GALEX) Deep Imaging Survey. This dataset provides a multi-wavelength look at the evolution of the attenuation by dust, and here we compare a traditional measure of dust attenuation (L(TIR)/L(FUV)) to a diagnostic based on a recently-developed robust star formation rate (SFR) indicator, [H-alpha_obs+24-micron]/H-alpha_obs. With such data over multiple epochs, the evolution in the attenuation by dust with redshift can be assessed. We present results from the ELAIS-N1 and Lockman Hole regions at z~0.16, 0.24, 0.32 and 0.40. While the ensemble averages of both diagnostics are relatively constant from epoch to epoch, each epoch ind...

Moore, Carolynn A; Barlow, Rebecca J; Cohen, Seth A; Cook, David O; Johnson, L C; Kattner, ShiAnne M; Lee, Janice C; Staudaher, Shawn M

2010-01-01

 
 
 
 
141

A 2 kiloparsec accretion disk (?) inside a 17 kiloparsec H-alpha bar in the cooling flow cluster 2A 0335+096  

Science.gov (United States)

Observations of the central region of the galaxy cluster associated with 2A 0335+096, obtained in H-alpha, R, I, and b45 (4506 A with FWHM 355 A) using an 800 x 800-pixel CCD detector on the 4-m telescope at KPNO on December 27 and 30, 1986, are reported. The data are presented graphically and analyzed. Features discussed include a 17-kpc-long bar of H-alpha emission surrounded by filaments, a smaller elongated H-alpha structure (possibly an accretion disk) centered on the nucleus of the central galaxy, a secondary galaxy with a red H-alpha-bright nucleus located within the 17-kpc bar about 6 arcsec from the central-galaxy nucleus, and evidence for excess blue emission (indicating star formation at about 8 solar mass/yr in the cooling flow). From the presence of dust in the emission-line gas it is inferred that theoretical models based on preferential formation of low-mass stars may not be applicable to this object.

Romanishin, W.; Hintzen, Paul

1988-01-01

142

2 kiloparsec accretion disk (?) inside a 17 kiloparsec H-alpha bar in the cooling flow cluster 2A 0335+096  

International Nuclear Information System (INIS)

Observations of the central region of the galaxy cluster associated with 2A 0335+096, obtained in H-alpha, R, I, and b45 (4506 A with FWHM 355 A) using an 800 x 800-pixel CCD detector on the 4-m telescope at KPNO on December 27 and 30, 1986, are reported. The data are presented graphically and analyzed. Features discussed include a 17-kpc-long bar of H-alpha emission surrounded by filaments, a smaller elongated H-alpha structure (possibly an accretion disk) centered on the nucleus of the central galaxy, a secondary galaxy with a red H-alpha-bright nucleus located within the 17-kpc bar about 6 arcsec from the central-galaxy nucleus, and evidence for excess blue emission (indicating star formation at about 8 solar mass/yr in the cooling flow). From the presence of dust in the emission-line gas it is inferred that theoretical models based on preferential formation of low-mass stars may not be applicable to this object. 17 references.

1988-01-01

143

2 kiloparsec accretion disk (. ) inside a 17 kiloparsec H-alpha bar in the cooling flow cluster 2A 0335+096  

Energy Technology Data Exchange (ETDEWEB)

Observations of the central region of the galaxy cluster associated with 2A 0335+096, obtained in H-alpha, R, I, and b45 (4506 A with FWHM 355 A) using an 800 x 800-pixel CCD detector on the 4-m telescope at KPNO on December 27 and 30, 1986, are reported. The data are presented graphically and analyzed. Features discussed include a 17-kpc-long bar of H-alpha emission surrounded by filaments, a smaller elongated H-alpha structure (possibly an accretion disk) centered on the nucleus of the central galaxy, a secondary galaxy with a red H-alpha-bright nucleus located within the 17-kpc bar about 6 arcsec from the central-galaxy nucleus, and evidence for excess blue emission (indicating star formation at about 8 solar mass/yr in the cooling flow). From the presence of dust in the emission-line gas it is inferred that theoretical models based on preferential formation of low-mass stars may not be applicable to this object. 17 references.

Romanishin, W.; Hintzen, P.

1988-01-01

144

HiZELS: a high redshift survey of H-alpha emitters. II: the nature of star-forming galaxies at z=0.84  

CERN Document Server

New results from a large survey of H-alpha emission-line galaxies at z=0.84 using WFCAM/UKIRT and a custom narrow-band filter in the J band are presented as part of the HiZELS survey. Reaching an effective flux limit of 1e-16 erg/s/cm^2 in a comoving volume of 1.8e5 Mpc^3, this represents the largest and deepest survey of its kind ever done at z~1. There are 1517 potential line emitters detected across 1.4 sq.deg of the COSMOS and UKIDSS UDS fields, of which 743 are selected as H-alpha emitters. These are used to calculate the H-alpha luminosity function, which is well-fitted by a Schechter function with phi*=10^(-1.92+-0.10) Mpc^-3, L*=10^(42.26+-0.05)erg/s, and alpha=-1.65+-0.15. The integrated star formation rate density (SFRD) at z=0.845 is 0.15+-0.01 M_sun/yr/Mpc^3. The results robustly confirm a strong evolution of SFRD from the present day out to z~1 and then flattening to z~2, using a single star-formation indicator. Out to z~1, both the characteristic luminosity and space density of the H-alpha emitt...

Sobral, D; Geach, J E; Smail, Ian; Kurk, J; Cirasuolo, M; Casali, M; Ivison, R J; Coppin, K; Dalton, G B

2009-01-01

145

Obscured star formation at z = 0.84 with HiZELS: the relationship between star formation rate and H-alpha or ultra-violet dust extinction  

CERN Document Server

[Abridged] We compare H-alpha, ultraviolet (UV) and infrared (IR) indicators of star formation rate (SFR) for a sample of z = 0.84 galaxies from the High-z Emission Line Survey (HiZELS). Using multi-wavelength diagnostics, we estimate that 5 - 11 per cent of H-alpha emitters at this redshift are active galactic nuclei. We detect 35 per cent of the H-alpha emitters individually at 24 microns, and stack the star-forming emitters on deep 24-micron images in order to calculate the typical SFRs of our galaxies. These are compared to the observed H-alpha line fluxes in order to estimate the extinction at z = 0.84, and we find a significant increase in dust extinction for galaxies with higher SFRs. We demonstrate that the local relationship between SFR and extinction is suitable for our sample, and attribute the overall increase in dust extinction for z = 0.84 galaxies to an increase in the average SFR, rather than to a change in dust properties. We calculate the UV extinction, and find a similar dependence on SFR, ...

Garn, Timothy; Best, Philip N; Geach, James E; Smail, Ian; Cirasuolo, Michele; Dalton, Gavin B; Dunlop, James S; McLure, Ross J; Farrah, Duncan

2009-01-01

146

The FMOS-COSMOS survey of star-forming galaxies at z ~ 1.6 I. H\\alpha -based star formation rates and dust extinction  

CERN Multimedia

We present first results from a near-infrared spectroscopic survey of the COSMOS field, using the Fiber Multi-Object Spectrograph (FMOS) on the Subaru telescope, designed to characterize the star-forming galaxy population at 1.4H\\alpha\\ in emission between 1.6-1.8\\mu m with $f_H\\alpha\\ \\gtrsim 4 \\times 10^{-17} ergs cm^{-2} s^{-1}$. Here, we specifically focus on 271 sBzK-selected galaxies that yield a H\\alpha\\ detection thus providing a redshift and emission-line luminosity to establish the relation between star formation rate (SFR) and stellar mass. With further J-band spectroscopy for 89 of these, the level of dust extinction is assessed by measuring the Balmer decrement using co-added spectra. We find that the extinction (0.6\\lesssim A_H\\alpha\\ \\lesssim 2.5) rises with stellar mass and is elevated at high masses compared to low-redshift galaxies. Using this subset of the spectroscopic sample, we further find that the differential extinction b...

Kashino, D; Rodighiero, G; Renzini, A; Arimoto, N; Daddi, E; Lilly, S J; Sanders, D B; Kartaltepe, J; Zahid, H J; Nagao, T; Sugiyama, N; Capak, P; Carollo, C M; Chu, J; Hasinger, G; Ilbert, O; Kajisawa, M; Kewley, L J; Koekemoer, A M; Kova?, K; Fèvre, O Le; Masters, D; McCracken, H J; Onodera, M; Scoville, N; Strazzullo, V; Symeonidis, M; Taniguchi, Y

2013-01-01

147

Synthesis of H-alpha absorption in old stellar systems: Formation of the cluster red sequence by "Downsizing"  

CERN Document Server

We compute population synthesis models for the variation of H-alpha absorption indices (HaA and HaF), as a function of age and metallicity in old stellar systems. The models are based on the STELIB spectral library, and defined at resolution of 3 Angstrom FWHM. The indices are found to be highly sensitive to age variation, with only moderate response to metallicity. For galaxies uncontaminated by nebular emission, our HaA index is more powerful in breaking the age/metallicity degeneracy than H-beta or H-gamma_F. Using a sample of red cluster galaxies carefully selected to exclude objects with emission, we find a steep decline of HaA with velocity dispersion (slope -0.75 +/- 0.07 Angstrom/dex). The slope can be translated to constraints on age and metallicity scaling relations, incorporating measurement and model errors. If the HaA-sigma slope is due only to age, we obtain Age proportional to sigma^{0.95 +/- 0.12}. Because HaA depends quite weakly on [Fe/H], a metallicity interpretation would require Fe/H prop...

Smith, R J

2005-01-01

148

Multiwavelength Signatures of Magnetic Activity from Young Stellar Objects in the LkH\\alpha101 Cluster  

CERN Multimedia

[abridged] We describe the results of our multi-wavelength observing campaign on the young stellar objects in the LkH$\\alpha$101 cluster. Our simultaneous X-ray and multi-frequency radio observations are unique in providing simultaneous constraints on short-timescale variability at both wavelengths as well as constraints on the thermal or nonthermal nature of radio emission from young stars. Focussing in on radio-emitting objects and the multi-wavelength data obtained for them, we find that multi-frequency radio data indicate nonthermal emission even in objects with infrared evidence for disks. We find radio variability on timescales of decades, days and hours. About half of the objects with X-ray and radio detections were variable at X-ray wavelengths, despite lacking large-scale flares or large variations. Variability appears to be a bigger factor affecting radio emission than X-ray emission. A star with infrared evidence for a disk, [BW88]~3, was observed in the decay phase of a radio flare. In this object...

Osten, R A

2008-01-01

149

Circumstellar $H-\\alpha$ from SN 1994D and future Type Ia supernovae an observational test of progenitor models  

CERN Document Server

Searching for the presence of circumstellar material is currently the only direct way to discriminate between the different types of possible progenitor systems for Type Ia supernovae. We have therefore looked for narrow H-alpha in a high-resolution spectrum of the normal Type Ia supernova 1994D taken 10 days before maximum and only 6.5 days after explosion. We derive an upper limit of 2.0E-16 erg cm^{-2} s^{-1} for an unresolved emission line at the local H II region velocity. To estimate the limit this puts on wind density, we have made time-dependent photoionization calculations. Assuming spherical symmetry we find an upper limit of the mass loss rate which is roughly 1.5E-5 solar masses per year for a wind speed of 10 km s^{-1}. This limit can exclude only the highest-mass-loss-rate symbiotic systems as progenitors. We discuss the effect of asymmetry and assess the relative merits of early optical, radio and X-ray limits in constraining mass loss from Type Ia progenitors. We find that X-ray observations c...

Cumming, R J; Smith, L J; Pettini, M; King, D L

1996-01-01

150

STAR FORMATION PROPERTIES IN THE LOCAL VOLUME GALAXIES VIA H{alpha} AND FAR-ULTRAVIOLET FLUXES  

Energy Technology Data Exchange (ETDEWEB)

A distance-limited sample of 869 objects from the Updated Nearby Galaxy Catalog is used to characterize the star formation status of the Local Volume population. We present a compiled list of 1217 star formation rate (SFR) estimates for 802 galaxies within 11 Mpc, derived from the H{alpha} imaging surveys and the GALEX far-ultraviolet survey. We briefly discuss some basic scaling relations between SFR and luminosity, morphology, H I mass, surface brightness, and the environment of the galaxies. About 3/4 of our sample consist of dwarf galaxies, for which we offer a more refined classification. We note that the specific SFR of nearly all luminous and dwarf galaxies does not exceed the maximum value: log (SFR/L{sub K} ) = -9.4 [yr{sup -1}]. Most spiral and blue dwarf galaxies have enough time to generate their stellar mass during the cosmological time, T{sub 0}, with the observed SFRs. They dispose of a sufficient amount of gas to support their present SFRs over the next T{sub 0} term. We note that only a small fraction of BCD, Im, and Ir galaxies (about 1/20) proceed in a mode of vigorous starburst activity. In general, the star formation history of spiral and blue dwarf galaxies is mainly driven by their internal processes. The present SFRs of E, S0, and dSph galaxies typically have 1/30-1/300 of their former activity.

Karachentsev, Igor D.; Kaisina, Elena I., E-mail: ikar@sao.ru, E-mail: kei@sao.ru [Special Astrophysical Observatory, Russian Academy of Sciences, Nizhnij Arkhyz, Karachai-Cherkessian Republic 369167 (Russian Federation)

2013-09-15

151

The Stellar Parameters and Evolutionary State of the Primary in the d'-Symbiotic System StH\\alpha190  

CERN Multimedia

We report on a high-resolution, spectroscopic stellar parameter and abundance analysis of a d' symbiotic star: the yellow component of StH\\alpha190. This star has recently been discovered, and confirmed here, to be a rapidly rotating (vsini=100 km/s) subgiant, or giant, that exhibits radial-velocity variations of probably at least 40 km/s, indicating the presence of a companion (a white dwarf star). It is found that the cool stellar component has Teff=5300K and log g=3.0. The iron and calcium abundances are close to solar, however, barium is overabundant, relative to Fe and Ca, by about +0.5 dex. The barium enhancement reflects mass-transfer of s-process enriched material when the current white dwarf was an asymptotic giant branch (AGB) star. The past and future evolution of this binary system depends critically on its current orbital period, which is not yet known. Concerted and frequent radial-velocity measurements are needed to provide crucial physical constraints to this d' symbiotic system.

Smith, V V; Cunha, K; Smith, Verne V.; Pereira, Claudio B.; Cunha, Katia

2001-01-01

152

Large-Amplitude Oscillation of an Erupting Filament as Seen in EUV, H-alpha and Microwave Observations  

CERN Multimedia

We present multiwavelength observations of a large-amplitude oscillation of a polar crown filament on 15 October 2002. The oscillation occurred during the slow rise (about 1 km/s) of the filament. It completed three cycles before sudden acceleration and eruption. The oscillation and following eruption were clearly seen in observations recorded by the Extreme-Ultraviolet Imaging Telescope onboard SOHO. The oscillation was seen only in a part of the filament, and it appears to be a standing oscillation rather than a propagating wave. The period of oscillation was about two hours and did not change significantly during the oscillation. We also identified the oscillation as a "winking filament" in the H-alpha images taken by the Flare Monitoring Telescope, and as a spatial displacement in 17 GHz microwave images from Nobeyama Radio Heliograph (NoRH). The filament oscillation seems to be triggered by magnetic reconnection between a filament barb and nearby emerging magnetic flux as was evident from the MDI magneto...

Isobe, H; Asai, A; Jain, R

2007-01-01

153

Equivalence Testing Mobile Apps  

Directory of Open Access Journals (Sweden)

Full Text Available Mobile apps are often developed and then evolved on more than one mobile operating system. For the publisher of such apps, the problem is how to ensure equivalence of the product on the various platforms, in the sense of acting equivalently with respect to a test set. In this paper we present an approach that tackles this problem from two directions: architecture and testing. First we will explain the role and pitfalls of reference architectures. Then we will present our equivalence testing framework. It is based on mocking components of the target implementation. Instead of implementing mock components for all platforms, our approach is to implement these mocks only once and run them on a central server. On the tested target device, stub components are injected that forward to their server-based counterparts. Thus the exactly same test code is applied to all platform specific implementations.

Denzler Christoph; Kröni Daniel; Moschko Maxim

2012-01-01

154

Beyond Network Equivalence  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In earlier work, we described an equivalence result for network capacity. Roughly, that result is as follows. Given a network of noisy, memoryless, point-to-point channels, replace each channel by a noiseless, memoryless bit pipe of the same capacity yields a new network such that any collection of ...

Koetter, Ralf; Effros, Michelle; Medard, Muriel

155

Radioactive waste equivalence  

International Nuclear Information System (INIS)

The report reviews, for the Member States of the European Community, possible situations in which an equivalence concept for radioactive waste may be used, analyses the various factors involved, and suggests guidelines for the implementation of such a concept. Only safety and technical aspects are covered. Other aspects such as commercial ones are excluded. Situations where the need for an equivalence concept has been identified are processes where impurities are added as a consequence of the treatment and conditioning process, the substitution of wastes from similar waste streams due to the treatment process, and exchange of waste belonging to different waste categories. The analysis of factors involved and possible ways for equivalence evaluation, taking into account in particular the chemical, physical and radiological characteristics of the waste package, and the potential risks of the waste form, shows that no simple all-encompassing equivalence formula may be derived. Consequently, a step-by-step approach is suggested, which avoids complex evaluations in the case of simple exchanges

1990-01-01

156

PATHOGEN EQUIVALENCY COMMITTEE (PEC)  

Science.gov (United States)

The U.S. Environmental Protection Agency created the PEC in 1985 to make recommendations to EPA and State managers on the equivalency of unproven sewage sludge disinfection technologies/processes to either a Process to Significantly Reduce Pathogens (PSRP) or a Process to Further...

157

Resonance width distribution for open quantum systems  

CERN Multimedia

Recent measurements of resonance widths for low-energy neutron scattering off heavy nuclei show large deviations from the standard Porter-Thomas distribution. We propose a new resonance width distribution based on the random matrix theory for an open quantum system. Two methods of derivation lead to a single analytical expression; in the limit of vanishing continuum coupling, we recover the Porter-Thomas distribution. The result depends on the ratio of typical widths $\\Gamma$ to the energy level spacing $D$ via the dimensionless parameter $\\kappa=(\\pi\\Gamma/2D)$. The new distribution suppresses small widths and increases the probabilities of larger widths.

Shchedrin, Gavriil

2011-01-01

158

H-alpha Observations of a Large Sample of Galaxies at z~2: Implications for Star Formation in High Redshift Galaxies  

CERN Multimedia

Using H-alpha spectra of 114 rest-frame UV-selected galaxies at z~2, we compare inferred star formation rates (SFRs) with those determined from the UV continuum luminosity. After correcting for extinction using standard techniques based on the UV continuum slope, we find excellent agreement between the indicators, with = 31 Msun/yr and = 29 Msun/yr. The agreement between the indicators suggests that the UV luminosity is attenuated by an typical factor of ~4.5 (with a range from no attenuation to a factor of ~100 for the most obscured object in the sample), in good agreement with estimates of obscuration from X-ray, radio and mid-IR data. The H-alpha luminosity is attenuated by a factor of ~1.7 on average, and the maximum H-alpha attenuation is a factor of ~5. In agreement with X-ray and mid-IR studies, we find that the SFR increases with increasing stellar mass and at brighter K magnitudes, to ~ 60 Msun/yr for galaxies with K10^11 Msun) have had higher SFRs in the past.

Erb, D K; Shapley, A E; Pettini, M; Reddy, N A; Adelberger, K L; Erb, Dawn K.; Steidel, Charles C.; Shapley, Alice E.; Pettini, Max; Reddy, Naveen A.; Adelberger, Kurt L.

2006-01-01

159

Spitzer IRAC observations of newly-discovered planetary nebulae from the Macquarie-AAO-Strasbourg H-alpha Planetary Nebula Project  

CERN Multimedia

We compare H-alpha, radio continuum, and Spitzer Space Telescope (SST) images of 58 planetary nebulae (PNe) recently discovered by the Macquarie-AAO-Strasbo- urg H-alpha PN Project (MASH) of the SuperCOSMOS H-alpha Survey. Using InfraRed Array Camera (IRAC) data we define the IR colors of PNe and demonstrate good isolation between these colors and those of many other types of astronomical object. The only substantive contamination of PNe in the color-color plane we illustrate is due to YSOs. However, this ambiguity is readily resolved by the unique optical characteristics of PNe and their environs. We also examine the relationships between optical and MIR morphologies from 3.6 to 8.0um and explore the ratio of mid-infrared (MIR) to radio nebular fluxes, which is a valuable discriminant between thermal and nonthermal emission. MASH emphasizes late evolutionary stages of PNe compared with previous catalogs, enabling study of the changes in MIR and radio flux that attend the aging process. Spatially integrated M...

Cohen, Martin; Green, Anne J; Murphy, Tara; Miszalski, Brent; Frew, David J; Meade, Marilyn R; Babler, Brian; Indebetouw, Remy; Whitney, Barbara A; Watson, Christer; Churchwell, Edward B; Watson, Douglas F

2007-01-01

160

Multi-Object Near-IR H-alpha Spectroscopy of z~1 star-forming galaxies in the HDF-N  

CERN Document Server

We present preliminary results from a programme to obtain multi-object near-infrared spectroscopy of galaxies at redshifts $0.7H-alpha in galaxies at $z\\sim1$. We aim to address the true star formation history of the universe at this epoch: potentially the peak period of star formation activity. H-alpha is the same star formation measure used at low redshift, and hence we can trace star formation without the systematic uncertainties of using different calibrators in different redshift bins, or the extreme dust extinction in the rest-UV. CIRPASS has been successfully demonstrated in multi-object mode on the AAT and WHT. Here we present preliminary results from one of our fields, the Hubble Deep Field North, observed with the WHT. With 150 fibres deployed over an unvignetted field of $\\sim15$arcmin, we have several detections of H-alpha from star forming galaxies at $0.8<...

Doherty, M; Sharp, R; Dalton, G B; Parry, I; Lewis, I; MacDonald, E; Wolf, C; Hippelein, H; Doherty, Michelle; Bunker, Andrew; Sharp, Robert; Dalton, Gavin; Parry, Ian; Lewis, Ian; Donald, Emily Mac; Wolf, Christian; Hippelein, Hans

2004-01-01

 
 
 
 
161

Adjustable Width Mattress with Relief Portions  

UK PubMed Central (United Kingdom)

A mattress assembly includes an inner core assembly 48 including a core portion 49 having a head end and a foot end defining a core longitudinal length a left width adjustment portion 56 comprising a plurality of left width adjustment bladders 60, the left width adjustment portion extending laterally away from a left side of the core portion a right width adjustment portion 58 comprising a plurality of right width adjustment bladders 62, the right width adjustment portion extending laterally away from the right side of the core portion the left and right width adjustment portions each having a head end substantially longitudinally aligned with the head end of the core portion and extending footwardly a longitudinal distance less than the core longitudinal length thereby defining left and right relief portions 66, 68.

CHAMBERS KENITH W; BUTTER MARY; BISH SUZANNE M

162

Detonation cell widths in hydrogen-air-diluent mixtures  

International Nuclear Information System (INIS)

In this paper I report on the influence of steam and carbon dioxide on the detonability of hydrogen-air mixtures. Data were obtained on the detonation cell width in a heated detonation tube that is 0.43 m in diameter and 13.1 m long. The detonation cell widths were correlated using a characteristic length calculated from a chemical kinetic model. The addition of either diluent to a hydrogen-air mixture increased the cell width for all equivalence ratios. For equal diluent concentrations, however, carbon dioxide not only yielded larger increases in the cell width than steam, but its efficacy relative to steam was predicted to increase with increasing concentration. The range of detonable hydrogen concentrations in a hydrogen-air mixture initially at 1 atm pressure was found to be between 11.6 percent and 74.9 percent for mixtures at 20 degree C and 9.4 percent and 76.9 percent for mixtures at 100 degree C. The detonation limit was between 38.8 percent and 40.5 percent steam for a stoichiometric hydrogen-air-steam mixture initially at 100 degree C and 1 atm. 10 refs., 4 figs., 1 tab

1990-01-01

163

Detonation cell widths in hydrogen-air-diluent mixtures  

Energy Technology Data Exchange (ETDEWEB)

In this paper I report on the influence of steam and carbon dioxide on the detonability of hydrogen-air mixtures. Data were obtained on the detonation cell width in a heated detonation tube that is 0.43 m in diameter and 13.1 m long. The detonation cell widths were correlated using a characteristic length calculated from a chemical kinetic model. The addition of either diluent to a hydrogen-air mixture increased the cell width for all equivalence ratios. For equal diluent concentrations, however, carbon dioxide not only yielded larger increases in the cell width than steam, but its efficacy relative to steam was predicted to increase with increasing concentration. The range of detonable hydrogen concentrations in a hydrogen-air mixture initially at 1 atm pressure was found to be between 11.6 percent and 74.9 percent for mixtures at 20{degree}C and 9.4 percent and 76.9 percent for mixtures at 100{degree}C. The detonation limit was between 38.8 percent and 40.5 percent steam for a stoichiometric hydrogen-air-steam mixture initially at 100{degree}C and 1 atm. 10 refs., 4 figs., 1 tab.

Stamps, D.W.

1990-01-01

164

Equivalence Principle in Cosmology  

CERN Document Server

We analyse the Einstein equivalence principle (EEP) for a Hubble observer in Friedmann-Lemaitre-Robertson-Walker spacetime. We show that the affine structure of light cone in the FLRW spacetime should be treated locally in terms of the optical metric which is not reduced to the Minkowski metric due to the non-uniform parametrization of the local equations of light propagation with the proper time of the observer's clock. The physical consequence of this difference is that the Doppler shift of radio waves measured locally, is affected by the Hubble expansion.

Kopeikin, Sergei

2013-01-01

165

Nanosecond pulsed generator with regulable pulse width  

International Nuclear Information System (INIS)

In this paper the nanosecond pulse signal generator with regulable pulse width as well as its apparatus structure, operating principle, circuit design, technica index and measure of anti-jamming will be introduced in brief. By combine digital integrate circuits with analog circuit, nanosecond pulse signal of two kinds of different pulse width and regulable pulse width at the same time is accomplished in the apparatus

2003-01-01

166

On convex bodies of constant width  

CERN Multimedia

We present an alternative proof of the following fact: the hyperspace of compact closed subsets of constant width in $\\mathbb R^n$ is a contractible Hilbert cube manifold. The proof also works for certain subspaces of compact convex sets of constant width as well as for the pairs of compact convex sets of constant relative width. Besides, it is proved that the projection map of compact closed subsets of constant width is not 0-soft in the sense of Shchepin, in particular, is not open.

Bazylevych, L E

2004-01-01

167

Partial nucleon escape widths of giant resonances  

International Nuclear Information System (INIS)

Method and results of calculation of the partial nucleon escape widths of various giant resonances are presented. The comparison with relevant experimental data and the results of other theoretical approaches is given where it is possible. The partial widths for the direct proton decay of the Gamow-Teller resonance in Sn isotopes are given special attention. (orig.)

1994-03-07

168

Direct measurement of the W boson width  

International Nuclear Information System (INIS)

This Letter describes a direct measurement of the W boson decay width, ?(W), using the high-mass tail of the transverse mass spectrum of W?e? decays recorded by the Collider Detector at Fermilab. We find ?(W)=2.11±0.28(stat) ± 0.16(syst) GeV and compare this direct measurement with indirect means of obtaining the width.

1995-01-01

169

In vitro skin equivalents  

Directory of Open Access Journals (Sweden)

Full Text Available Sun Pharmaceutical Advanced research Centre (SPARC),17/B, Off Mahakali caves road, Mahal Indl. Estate,Andheri (E), Mumbai-400 093,INDIA,email : hemantjoshee@sify.comTo assess the role of genes required for skin organogenesis, tissue regeneration and homeostasis, in vitro skin equivalents composed of primary cells or cell lines, respectively. In these organotypic cocultures keratinocytes generate a normal epidermis irrespective of the species and tissue origin of fibroblasts. The combination of cells derived from mouse and human tissues facilitates the identification of the origin of compounds involved in epidermal tissue reconstitution and thus the precise analysis of growth regulatory mechanisms.Keywords: In vitro models, keratinocytes, fibroblasts, skin re-epithelialization, in situ hybridization, cadaver skin

Hemant P. Joshi

2006-01-01

170

Simulation vs. Equivalence  

CERN Document Server

For several semirings S, two weighted finite automata with multiplicities in S are equivalent if and only if they can be connected by a chain of simulations. Such a semiring S is called "proper". It is known that the Boolean semiring, the semiring of natural numbers, the ring of integers, all finite commutative positively ordered semirings and all fields are proper. The semiring S is Noetherian if every subsemimodule of a finitely generated S-semimodule is finitely generated. First, it is shown that all Noetherian semirings and thus all commutative rings and all finite semirings are proper. Second, the tropical semiring is shown not to be proper. So far there has not been any example of a semiring that is not proper.

Esik, Zoltan

2010-01-01

171

Influence of chamber width on cokemaking  

Energy Technology Data Exchange (ETDEWEB)

During recent decades the worldwide accepted standard for coke oven width has been 450 mm. Two new coke ovens constructed with widths of 450 and 600 mm were used to investigate the exponential relationship between coking time and chamber width. A relationship was found between coking time and flue temperature as a function of oven width. Extended residence times in the wider oven led to improved shrinkage of the coke cake, to lower power demand of the coke pushing machine, and to improved strength of the coke. The exponential function expressing the interdependence of chamber width and coking time was found to have an exponent power of 1.35 shifting to 1.20 as flue temperature increased. (CKK)

Rohde, W.; Habermehl, D.; Flockenhaus, C.

1982-01-01

172

Neural Networks with Finite Width Action Potentials  

CERN Multimedia

The significance of having finite widths of action potentials in integrate and fire neural networks is investigated. Models suggested by Hopfield and Herz [1] with zero action potential has been generalized to include pulse shapes of arbitrary widths and shapes. The convergence to limit cycle is examined both analytically and in simulation experiments. Hopfield's proof for nonleaking models has been extended nontrivially to the case of finite widths. It is pointed out that the concept of simultaneity in such networks maybe subject to bin widths in simulation experiments. The effects of varying the shape of the action potential and its width are examined. The roles of the magnitude of a leaking resistance connected to the neurons, a common external current and synaptic currents between neighbors are also examined and found to bear important consequences to the dynamical development of the network.

Shafee, F

2001-01-01

173

Stuttering Equivalence for Parity Games  

CERN Multimedia

We study the process theoretic notion of stuttering equivalence in the setting of parity games. We demonstrate that stuttering equivalent vertices have the same winner in the parity game. This means that solving a parity game can be accelerated by minimising the game graph with respect to stuttering equivalence. While, at the outset, it might not be clear that this strategy should pay off, our experiments using typical verification problems illustrate that stuttering equivalence speeds up solving parity games in many cases.

Cranen, Sjoerd; Willemse, Tim A C

2011-01-01

174

Biologic width dimensions--a systematic review.  

UK PubMed Central (United Kingdom)

BACKGROUND: Consideration of the biologic width in restorative dentistry seems to be important for maintaining periodontal health. OBJECTIVE: To evaluate the dimensions of the biologic width in humans. MATERIALS AND METHODS: A systematic literature search was performed for publications published by 28 September 2012 using five different electronic databases; this search was complemented by a manual search. Two reviewers conducted the study selection, data collection, and validity assessment. The PRISMA criteria were applied. From 615 titles identified by the search strategy, 14 publications were included and six were suitable for meta-analyses. RESULTS: Included studies were published from the years 1924 to 2012. They differed with regard to measurements of the biologic width. Mean values of the biologic width obtained from two meta-analyses ranged from 2.15 to 2.30 mm, but large intra- and inter-individual variances (subject sample range: 0.2 - 6.73 mm) were observed. The tooth type and site, the presence of a restoration and periodontal diseases/surgery affected the dimensions of the biologic width. Pronounced heterogeneity among studies regarding methods and outcome measures exists. CONCLUSIONS: No universal dimension of the biologic width appears to exist. Establishment of periodontal health is suggested prior to the assessment of the biologic width within reconstructive dentistry.

Schmidt JC; Sahrmann P; Weiger R; Schmidlin PR; Walter C

2013-05-01

175

Equivalence of superspace groups.  

UK PubMed Central (United Kingdom)

An algorithm is presented which determines the equivalence of two settings of a (3 + d)-dimensional superspace group (d = 1, 2, 3). The algorithm has been implemented as a web tool findssg on SSG(3+d)D, providing the transformation of any user-given superspace group to the standard setting of this superspace group in SSG(3+d)D. It is shown how the standard setting of a superspace group can be directly obtained by an appropriate transformation of the external-space lattice vectors (the basic structure unit cell) and a transformation of the internal-space lattice vectors (new modulation wavevectors are linear combinations of old modulation wavevectors plus a three-dimensional reciprocal-lattice vector). The need for non-standard settings in some cases and the desirability of employing standard settings of superspace groups in other cases are illustrated by an analysis of the symmetries of a series of compounds, comparing published and standard settings and the transformations between them. A compilation is provided of standard settings of compounds with two- and three-dimensional modulations. The problem of settings of superspace groups is discussed for incommensurate composite crystals and for chiral superspace groups.

van Smaalen S; Campbell BJ; Stokes HT

2013-01-01

176

Infinite-dimensional generalization of Kolmogorov widths  

CERN Document Server

Recently the theory of widths of Kolmogorov-Gelfand has received a great deal of interest due to its close relationship with the newly born area of Compressive Sensing in Signal Processing. However fundamental problems of the theory of widths in multidimensional Theory of Functions remain untouched, as well as analogous problems in the theory of multidimensional Signal Analysis. In the present paper we provide a multidimensional generalization of the original result of Kolmogorov about the widths of an "ellipsoidal sets" consisting of functions defined on an interval.

Kounchev, Ognyan

2011-01-01

177

New recommendations for dose equivalent  

International Nuclear Information System (INIS)

[en] In its report 39, the International Commission on Radiation Units and Measurements (ICRU), has defined four new quantities for the determination of dose equivalents from external sources: the ambient dose equivalent, the directional dose equivalent, the individual dose equivalent, penetrating and the individual dose equivalent, superficial. The rationale behind these concepts and their practical application are discussed. Reference is made to numerical values of these quantities which will be the subject of a coming publication from the International Commission on Radiological Protection, ICRP. (Author)

1985-01-01

178

Macroclumping as solution of the discrepancy between H{\\alpha} and P v mass loss diagnostics for O-type stars  

CERN Document Server

Recent studies of O-type stars demonstrated that discrepant mass-loss rates are obtained when different diagnostic methods are employed - fitting the unsaturated UV resonance lines (e.g. P v) gives drastically lower values than obtained from the H{\\alpha} emission. Wind clumping may be the main cause for this discrepancy. In a previous paper, we have presented 3-D Monte-Carlo calculations for the formation of scattering lines in a clumped stellar wind. In the present paper we select five O-type supergiants (from O4 to O7) and test whether the reported discrepancies can be resolved this way. In the first step, the analyses start with simulating the observed spectra with Potsdam Wolf-Rayet (PoWR) non-LTE model atmospheres. The mass-loss rates are adjusted to fit best to the observed H{\\alpha} emission lines. For the unsaturated UV resonance lines (i.e. P v) we then apply our 3-D Monte-Carlo code, which can account for wind clumps of any optical depths, a non-void inter-clump medium, and a velocity dispersion in...

Šurlan, B; Aret, A; Kubát, J; Oskinova, L M; Torres, A F

2013-01-01

179

The H$\\alpha$ line forming region of AB Aur spatially resolved at sub-AU with the VEGA/CHARA spectro-interferometer  

CERN Document Server

A crucial issue in star formation is to understand the physical mechanism by which mass is accreted onto and ejected by a young star. The visible spectrometer VEGA on the CHARA array can be an efficient means of probing the structure and the kinematics of the hot circumstellar gas at sub-AU. For the first time, we observed the Herbig Ae star AB Aur in the H$\\alpha$ emission line, using the VEGA low spectral resolution on two baselines of the array. We computed and calibrated the spectral visibilities between 610 nm and 700 nm. To simultaneously reproduce the line profile and the visibility, we used a 1-D radiative transfer code that calculates level populations for hydrogen atoms in a spherical geometry and synthetic spectro-interferometric observables. We clearly resolved AB Aur in the H$\\alpha$ line and in a part of the continuum, even at the smallest baseline of 34 m. The small P-Cygni absorption feature is indicative of an outflow but could not be explained by a spherical stellar wind model. Instead, it f...

Perraut, K; Mourard, D; Rajabi, S; Bacciotti, F; Bério, Ph; Bonneau, D; Chesneau, O; Clausse, J M; Delaa, O; Marcotto, A; Roussel, A; Spang, A; Stee, Ph; Tallon-Bosc, I; McAlister, H; Brummelaar, T ten; Sturmann, J; Sturmann, L; Turner, N; Farrington, C; Goldfinger, P J

2010-01-01

180

High-energy break-up of 6Li as a tool to study the Big-Bang nucleosynthesis reaction 2H(alpha,gamma)6Li  

CERN Document Server

The recently claimed observations of non-negligible amounts of 6Li in old halo stars have renewed interest in the Big-Bang Nucleosynthesis (BBN) of 6Li. One important ingredient in the predicted BBN abundance of 6Li is the low-energy 2H(alpha,gamma)6Li cross section. Up to now, the only available experimental result for this cross section showed an almost constant astrophysical S-factor below 400 keV, contrary to theoretical expectations. We report on a new measurement of the 2H(alpha,gamma)6Li reaction using the break-up of 6Li at 150 A MeV. Even though we cannot separate experimentally the Coulomb contribution from the nuclear one, we find clear evidence for Coulomb-nuclear interference by analyzing the scattering-angular distributions. This is in-line with our theoretical description which indicates a drop of the S_24-factor at low energies as predicted also by most other models. Consequently, we find even lower upper limits for the calculated primordial 6Li abundance than before.

Hammache, F; Typel, S; Galaviz, D; Sümmerer, K; Coc, A; Uhlig, F; Attallah, F; Caamano, M; Cortina, D; Geissel, H; Hellström, M; Iwasa, N; Kiener, J; Koczon, P; Kohlmeyer, B; Mohr, P; Schwab, E; Schwarz, K; Schümann, F; Senger, P; Sorlin, O; Tatischeff, V; Thibaud, J P; Vangioni, E; Wagner, A; Walus, W

2010-01-01

 
 
 
 
181

Neutron beam compressors for pulse width reduction  

International Nuclear Information System (INIS)

In the context of intensity and resolution optimization of a neutron time-of-flight spectrometer several methods of beam width reduction at the chopper are considered aiming at a reduction of the neutron pulse width at minimum loss of intensity. The most advantageous technique discussed uses a double-trumpet arrangement in which the chopper is placed in between converging and diverging neutron guide sections. 7 refs., 1 fig

1989-01-01

182

Appropriate energy window width for gamma camera  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction: Scatter radiation is one of the major sources of error in nuclear medicine data processing. Different methods of scatter correction have been introduced in order to improve the quality of data. However the best method is to avoid recording of scatter photons in acquisition. The only difference between scattered and non-scattered photons is the energy. Pulse height analyzer is the only option available to discriminate primary photons from scattered ones. Energy resolution of the gamma camera is gradually improving consequently the energy window width has to be decreased accordingly. In this study we tried to determine the most appropriate energy window width for present gamma camera systems. Methods and Materials: Since it is not possible to retrieve the data spectrum from the most of the gamma camera systems, a simple method was developed to extract the data from the image of the energy spectrum. Using a scatter phantom different level of scatter and count rate were generated and corresponding energy spectrum data were analyzed. It was assumed that around the peak of the spectrum, the primary photons obey a Gaussian distribution. Results: The data were analyzed using three different methods. All methods prove that the optimum window width regarding the present gamma camera energy resolution is 15%. At this level, the scattered radiation is decreased to 5%. In comparison to the conventional widow width of 20%, the sensitivity does not change dramatically. Conclusion: At the present, for most gamma camera, the energy window width of 20% is recommended. However occasionally energy window width of 15% and 25% are also used. In this study the energy spectrum at different levels of scatter were analyzed and the most suitable energy window width was found to be 15% for the gamma camera having approximate energy resolution of 11%. At this window setting the scatter decreases to 5% of the total counts recorded. Visually the quality of the images dose not improves significantly. However accuracy of data quantification improve significantly.

Jabbari N; Rajabi H; Firouzabadi SH; Rastgoo F; Yaghoubi N; Bitarafan Rajabi A; Hashemi Malayeri B

2004-01-01

183

Appropriate energy window width for gamma camera  

International Nuclear Information System (INIS)

Introduction: scatter radiation is one of the major sources of error in nuclear medicine data processing. Different methods of scatter correction have been introduced in order to improve the quality of data. However the best method is to avoid recording of scatter photons in acquisition. The only difference between scattered and non-scattered photon is the energy. Pulse height analyzer is the only option available to discriminate primary photons from scattered ones. Energy resolutions of the gamma camera is gradually improving consequently the energy window width has to be decreased accordingly. In this study we tried to determine the most appropriate energy window width for present gamma camera systems. Methods and materials: since it is not possible to retrieve the data spectrum from the most of the gamma camera systems a simple method was developed to extract the data from the image of the energy spectrum. Using a scattered phantom different level of scatter and count rate were generated and corresponding energy spectrum data were analyzed. It was assumed that around the peak of the spectrum the primary photons obey a Gaussian distribution. Results: the data were analyzed using three different methods. All methods proved that the optimum window width regarding the present gamma camera energy resolution is 15%. At this level the scattered radiation is decreased to 5%. In comparison to the conventional window width of 20% the sensitivity does not change dramatically. Conclusion: at the present, for the most gamma camera the energy window width of 20% is recommended. However occasionally energy window width of 15 % and 25% are also used. In this study the energy spectrum at different levels of scatter were analyzed and the most suitable energy window width was found to be 15% for the gamma camera having approximate energy resolution of 11%. At this window setting the scatter decreases to 5% of the total counts recorded. Visually the quality of images does not improves significantly. However accuracy of data quantification improve significantly.

2004-01-01

184

Ambient dose equivalent and directional dose equivalent instruments  

International Nuclear Information System (INIS)

According to definitions of the new operational radiation quantities for environmental (area) monitoring recommended by the International Commission of Radiation Units and Measurements (ICRU) report 39, a spherical ambient dose equivalent meter and a parallel-plane directional dose equivalent meter were designed and developed. Experimental measurements for main performances and calibrations for response factors were made.

1991-01-01

185

Coastal dune behaviour at different beach widths  

Science.gov (United States)

Along the Dutch coastline, sand dunes form a natural defence against the sea. Together with the size of the beach, dune dimensions determine whether coastal safety requirements are met. Dunes grow via onshore transport of sediment by wind and erode mainly through the impact of sea waves during storms. Previous studies show that both dune growth and erosion are influenced by beach dimensions. A wide beach (500 m) is expected to provide more sediment for onshore transport and to dissipate more wave energy than a narrow beach (50 m). Hence, all other factors being equal, dune growth is likely to be higher on wide beaches than on narrow beaches. This study quantifies the relation between dune behaviour and beach width. Results will be used to improve and test predictive modelling of shoreline development. The combined effect of beach dimensions on dune behaviour was studied by comparing changes in dune volume at beaches of different widths. These volume changes represent the net effect of sediment accumulation and sediment loss of the dune. Yearly elevation measurements of 200 locations along the Dutch coastline were used, taken between 1960 and 2010. From these elevation measurements, beach width and yearly changes in dune volume were derived. Subsequently, measurements were grouped in beach width classes, each containing 100 paired observations of dune volume change and beach width. For these classes, the average and variability of volume changes were calculated. The results show a clear relation between beach width and dune behaviour. Going from narrow to wide beaches, average volume changes increase to a maximum. The beach width at which maximum growth is reached, differs per study area. For extremely wide beaches, average rates are lower. These cases are associated with development of transport inhibiting beach-topography. Inverse to the trend in volume changes, the variability of dune behaviour is highest on narrow beaches and decreases for wider beach classes. The positive relation between dune growth and beach width can be explained by both increased sediment input and reduced dune erosion at wider beaches. Further research is required to separate the effect of beach width on dune accretion from the effect on dune erosion.

Keijsers, Joep; Poortinga, Ate; De Groot, Alma; Riksen, Michel

2013-04-01

186

Electromagnetic perturbation of isobaric multiplet widths  

Energy Technology Data Exchange (ETDEWEB)

The manner in which isobaric multiplet decay widths are modified by electromagnetic interaction is studied. Arguments based on lowest-order perturbation theory are given that the widths should be quadratic in Tsub(z) if the multiplet is particle unstable in the absence of electromagnetism, but quartic for stable multiplets. The total widths of experimentally known multiplets are analyzed to determine their algebraic Tsub(z) dependence and both quadratic and non-quadratic cases are found. On the basis of a simple model of the Coulomb energy we then determine the masses of these multiplets in the absence of electromagnetism as well as the masses of the lowest T-allowed decay channels. We find the isobaric multiplet width equation to work in some cases while it has been found to be inconclusive in others; because of these uncertainties as to its correctness or range of applicability, we have constructed a soluble model in which tests may be carried out. To avoid difficulties such as the many-body problem, a non-local separable potential model simple enough to solve explicitly was chosen. Although the model is an oversimplification of the real nuclear situation it has been found to work very well. Namely, the quadratic quartic nature of the widths was borne out in the model.

Awin, A.M. (Al-Fateh Univ., Tripoli (Libya). Dept. of Mathematics)

1982-09-20

187

Line width of Josephson flux flow oscillators  

DEFF Research Database (Denmark)

A combination of wide-band electronic tunability and moderate free-running line width makes the Josephson flux flow oscillator (FFO) a perfect on-chip local oscillator for integrated submillimeter-wave SIS receivers. The possibility of FFO phase locking at all frequencies of interest has to be proven before one initiates real FFO applications. To achieve this goal a comprehensive set of line width measurements of the FFO operating in different regimes has been performed. FFOs with tapered shape have been successfully implemented in order to avoid the superfine resonant structure with voltage spacing of about 20 nV and extremely low differential resistance, recently observed in the IVC of the standard rectangular geometry. The obtained results have been compared with existing theories and FFO models in order to understand and possibly eliminate excess noise in the FFO. The intrinsic line width increases considerably at voltages above the boundary voltage because of the abrupt increase of the internal damping due to Josephson self-coupling. The influence of FFO parameters, in particular the differential resistances associated both with the bias current and with the applied magnetic field on the radiation line width, has been studied. Possible means of decreasing the free-running FFO line width will be discussed.

Koshelets, V.P.; Dmitriev, P.N.

2002-01-01

188

The Masses of Distant Galaxies from Optical Emission Line Widths  

CERN Multimedia

Promising methods for studying galaxy evolution rely on optical emission line width measurements to compare intermediate-redshift objects to galaxies with equivalent masses at the present epoch. However, emission lines can be misleading. We show empirical examples of galaxies with concentrated central star formation from a survey of galaxies in pairs; HI observations of these galaxies indicate that the optical line emission fails to sample their full gravitational potentials. We use simple models of bulge-forming bursts of star formation to demonstrate that compact optical morphologies and small half-light radii can accompany these anomalously narrow emission lines; thus late-type bulges forming on rapid (0.5-1 Gyr) timescales at intermediate redshift would exhibit properties similar to those of heavily bursting dwarfs. We conclude that some of the luminous compact objects observed at intermediate and high redshift may be starbursts in the centers of massive galaxies and/or bulges in formation.

Gillespie, E B; Gillespie, Elizabeth Barton; Zee, Liese van

2002-01-01

189

Improved V-shaped microcantilever width profile for sensing applications  

International Nuclear Information System (INIS)

In this work we have proposed an improvement in the shape of the V-shaped microcantilever by varying the width profile. In this paper we have studied the variation of resonant frequency as a function of changes in profile determined by the length of the microcantilever, keeping constant the active area for binding. It is observed that for the optimized nonlinear profile the angle at the tip is 91.410, more than twice the angle at the tip of the linear profile cantilever. The variation of the equivalent spring constant with changes in the profile is also studied. It is proposed that the optimum nonlinear profile cantilever has a spring constant of ?0.39 ?N ?m-1. The resonant frequency is obtained by using the Rayleigh-Ritz method, the deflection model and the SUGAR simulator. The results are compared and an improvement in the performance of the cantilever is observed.

2009-09-21

190

Improved V-shaped microcantilever width profile for sensing applications  

Energy Technology Data Exchange (ETDEWEB)

In this work we have proposed an improvement in the shape of the V-shaped microcantilever by varying the width profile. In this paper we have studied the variation of resonant frequency as a function of changes in profile determined by the length of the microcantilever, keeping constant the active area for binding. It is observed that for the optimized nonlinear profile the angle at the tip is 91.41{sup 0}, more than twice the angle at the tip of the linear profile cantilever. The variation of the equivalent spring constant with changes in the profile is also studied. It is proposed that the optimum nonlinear profile cantilever has a spring constant of {approx}0.39 {mu}N {mu}m{sup -1}. The resonant frequency is obtained by using the Rayleigh-Ritz method, the deflection model and the SUGAR simulator. The results are compared and an improvement in the performance of the cantilever is observed.

Subramanian, S; Gupta, Navneet, E-mail: dr.guptanavneet@gmail.co [Electrical and Electronics Engineering Group, Birla Institute of Technology and Science, Pilani, Rajasthan (India)

2009-09-21

191

Improved V-shaped microcantilever width profile for sensing applications  

Science.gov (United States)

In this work we have proposed an improvement in the shape of the V-shaped microcantilever by varying the width profile. In this paper we have studied the variation of resonant frequency as a function of changes in profile determined by the length of the microcantilever, keeping constant the active area for binding. It is observed that for the optimized nonlinear profile the angle at the tip is 91.41°, more than twice the angle at the tip of the linear profile cantilever. The variation of the equivalent spring constant with changes in the profile is also studied. It is proposed that the optimum nonlinear profile cantilever has a spring constant of ~0.39 µN µm-1. The resonant frequency is obtained by using the Rayleigh-Ritz method, the deflection model and the SUGAR simulator. The results are compared and an improvement in the performance of the cantilever is observed.

Subramanian, S.; Gupta, Navneet

2009-09-01

192

Finite width effects in top quark decays  

CERN Document Server

Motivated by evidence that the top quark mass lies near the bWZ threshold, we compute the decay rate for t\\rightarrow bWZ in the Standard Model, including the effects of the finite widths of the W and Z bosons. In the limit where the width effects are negligible, our results disagree with previously published calculations. We also examine the decay t\\rightarrow bWH. Although the widths induce a sizable enhancement near threshold for both decays, we find that the rates are still too small to be observed in the present generation of experiments. This means that detection of either mode in one of these experiments would be a signal of new physics.

Mahlon, G; Mahlon, Gregory; Parke, Stephen

1994-01-01

193

Influence of chamber width on cokemaking  

Energy Technology Data Exchange (ETDEWEB)

The advantages of a broader coke oven chamber are primarily the pushing of more coke per oven operation and the possibility of the selecting of an operation of 24 hours by high performance. At the experimental coke oven plant Prosper of the Bergbau-Forschung GmbH, the influence of the chamber width was studied in two ovens with widths of 450 and 600 mm. The correlation of the chamber width with the coking period is described by an exponential function whose exponent changes from 1.35 to 1.20 in the range of the applied heating flue temperatures of 1200 to 1400/sup 0/C. The production loss resulting from the nonlinearity can be compensated by a forced operation and due to the slightly higher bulk density of the coke formed.

Rohde, W.; Habermehl, D.; Wuennenberg, W.

1982-09-01

194

Constraints on widths of mixed pentaquark multiplets  

CERN Document Server

We determine constraints on the partial widths of mixed pentaquark multiplets in the framework of heavy baryon chiral perturbation theory (HB$\\chi$PT). The partial widths satisfy a GMO-type relation at leading order in HB$\\chi$PT, for arbitrary mixing. The widths of N(1440), N(1710), and $\\Theta(1540)$ are not consistent with ideal mixing, $\\theta_{N} = 35.3^{\\circ}$, but are consistent with $\\theta_{N} \\lesssim 25^{\\circ}$. Furthermore, there are parameter values in HB$\\chi$PT that produce such a mixing angle while allowing the identification of the mass spectrum above. As an alternative to non-ideal mixing, we also suggest reasons for giving up on N(1440) as a pure pentaquark state.

Mohta, V

2004-01-01

195

Resonant structure in the disks of spiral galaxies, using phase-reversals in streaming motions from 2D H{\\alpha} Fabry-Perot spectroscopy  

CERN Document Server

In this article we introduce a technique for finding resonance radii in a disk galaxy. We use a two-dimensional velocity field in H{\\alpha} emission obtained with Fabry-Perot interferometry, derive the classical rotation curve, and subtract it off, leaving a residual velocity map. As the streaming motions should reverse sign at corotation, we detect these reversals, and plot them in a histogram against galactocentric radius, excluding points where the amplitude of the reversal is smaller than the measurement uncertainty. The histograms show well-defined peaks which we assume to occur at resonance radii, identifying corotations as the most prominent peaks corresponding to the relevant morphological features of the galaxy (notably bars and spiral arm systems). We compare our results with published measurements on the same galaxies using other methods and different types of data.

Font, Joan; Epinat, Benoît; Fathi, Kambiz; Gutiérrez, Leonel; Hernandez, Olivier

2011-01-01

196

Determination of dihedral Psi angles in large proteins by combining NH(N)/C(alpha)H(alpha) dipole/dipole cross-correlation and chemical shifts.  

UK PubMed Central (United Kingdom)

We propose a strategy based on the combination of experimental NH(N)/C(alpha)H(alpha) dipole/dipole cross-correlated relaxation rates and chemical shift analysis for the determination of Psi torsion angles in proteins. The method allows the determination of a dihedral angle that is not easily accessible by nuclear magnetic resonance (NMR). The measurement of dihedral angle restraints can be used for structure calculation, which is known to improve the quality of NMR structures. The method is of particular interest in the case of large proteins, for which spectral assignment of the nuclear Overhauser effect spectra, and therefore straightforward structural determination, is out of reach. One advantage of the method is that it is reasonably simple to implement, and could be used in association with other methods aiming at obtaining structural information on complex systems, such as residual dipolar coupling measurements. An illustrative example is analyzed in the case of the 30-kDa protein 6-phosphogluconolactonase.

Loth K; Abergel D; Pelupessy P; Delarue M; Lopes P; Ouazzani J; Duclert-Savatier N; Nilges M; Bodenhausen G; Stoven V

2006-09-01

197

Pulse Width in a Rod Ejection Accident  

International Nuclear Information System (INIS)

An analysis of pulse width during a rod ejection accident was carried out to help in designing experiments to test fuel behaviour under reactivity initiated accident conditions. The analysis used calculations based on a three-dimensional neutron kinetics code, PARCS, and a model of a pressurized water reactor at both beginning and end of a fuel cycle. Results showed that pulse width varied inversely with the maximum increase in local fuel enthalpy and this is consistent with simple analytical models. The pulse width ranges from 25 to 100 ms for cases where the energy deposition goes from 30 to 10 cal/g. This is the range expected for the most likely REA for which the rod worth is just above prompt critical. It is the most likely REA since the probability of a particular rod worth decreases as one goes to higher rod worths above prompt-critical. The pulse width is 10-15 ms when the maximum increase in fuel enthalpy is in the range of 60-100 cal/g. It is at these enthalpies, or higher, where fuel failure might be expected. Hence, if tests are to be done to test the limits of a fuel pin, the pulse width in the tests should be in the range 10-15 ms. If the tests instead are done with pulse widths that are greater than 25 ms and fuel enthalpies that are in the range where failure is expected, e.g., 100 cal/g, there is an inconsistency

2003-04-30

198

Equivalence of stationary state ensembles  

CERN Multimedia

We show that the contact process in an ensemble with conserved total particle number, as simulated recently by Tome and de Oliveira [Phys. Rev. Lett. 86 (2001) 5463], is equivalent to the ordinary contact process, in agreement with what the authors assumed and believed. Similar conserved ensembles and equivalence proofs are easily constructed for other models.

Hilhorst, H J

2001-01-01

199

Equivalence between therm and gravity  

CERN Multimedia

We introduce the notion of thermal entropy density, and first demonstrated that there exists an equivalence between therm and gravity without depending on the definition of temperature or horizon. This equivalence indicates that gravity possesses thermal features, or, therm possesses effects of gravity. This may shed light on the nature of gravity.

Yang, Rong-Jia

2011-01-01

200

On a three way equivalence  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In view of the well known core equivalence results in atomless economies, coincidence of market game equilibrium allocations with competitive allocations is tantamount to a three way equivalence between market game mechanisms, competitive equilibria and the core. Based on this idea I propose an equi...

Koutsougeras, Léonidas

 
 
 
 
201

On the additivity of knot width  

CERN Document Server

It has been conjectured that the geometric invariant of knots in 3-space called the width is nearly additive. That is, letting w(K) denote the width of a knot K in 3-space, the conjecture is that for all knots K and K', w(K # K') = w(K) + w(K') - 2. We give an example of a knot K so that for K' any 2-bridge knot, it appears that w(K # K') = w(K) contradicting the conjecture.

Scharlemann, M; Scharlemann, Martin; Thompson, Abigail

2004-01-01

202

Beyond Hypertree Width: Decomposition Methods Without Decompositions  

CERN Multimedia

The general intractability of the constraint satisfaction problem has motivated the study of restrictions on this problem that permit polynomial-time solvability. One major line of work has focused on structural restrictions, which arise from restricting the interaction among constraint scopes. In this paper, we engage in a mathematical investigation of generalized hypertree width, a structural measure that has up to recently eluded study. We obtain a number of computational results, including a simple proof of the tractability of CSP instances having bounded generalized hypertree width.

Chen, H; Chen, Hubie; Dalmau, Victor

2005-01-01

203

Partial escape widths of giant resonances  

International Nuclear Information System (INIS)

[en] A method for calculation of the partial-nucleon-escape widths of giant resonances is proposed. The method is exact within the random-phase approximation in the continuum. A phenomenological description of the giant-resonance coupling to many-particle configurations is also given. This approach is applied to evaluation of the partial-nucleon-escape widths of various giant resonances in 208Pb parent nucleus. Our results are compared with the results of other theoretical approaches and with the relevant experimental data. (orig.)

1994-05-23

204

High Fin Width Mosfet Using Gaa Structure  

Directory of Open Access Journals (Sweden)

Full Text Available This paper describes the design and optimization of gate-all-around (GAA) MOSFETs structures. The optimum value of Fin width and Fin height are investigated for superior subthreshold behavior. Also the performance of Fin shaped GAA with gate oxide HfO2 are simulated and compared with conventional gate oxide SiO2 for the same structure. As a result, it was observed that the GAA with high K dielectric gate oxide has more possibility to optimize the Fin width with improved performance. All the simulations are performed on 3-D TCAD device simulator.

S.L.Tripathi; Ramanuj Mishra; R.A.Mishra

2012-01-01

205

The width difference of rho vector mesons  

CERN Multimedia

We compute the difference in decay widths of charged and neutral \\rho(770) vector mesons. The isospin breaking arising from mass differences of neutral and charged \\pi and \\rho mesons, radiative corrections to \\rho -> \\pi\\pi, and the \\rho -> \\pi\\pi\\gamma decays are taken into account. It is found that the width difference \\Delta \\Gamma_rho is very sensitive ot the isospin breaking in the $\\rho$ meson mass \\Delta m_\\rho. This result can be useful to test the correlations observed between the values of these parameters extracted from experimental data.

Flores-Baez, F V; Sanchez, G Toledo

2007-01-01

206

Bounding the Higgs Boson Width through Interferometry.  

UK PubMed Central (United Kingdom)

We study the change in the diphoton-invariant-mass distribution for Higgs boson decays to two photons, due to interference between the Higgs resonance in gluon fusion and the continuum background amplitude for gg???. Previously, the apparent Higgs mass was found to shift by around 100 MeV in the standard model in the leading-order approximation, which may potentially be experimentally observable. We compute the next-to-leading-order QCD corrections to the apparent mass shift, which reduce it by about 40%. The apparent mass shift may provide a way to measure, or at least bound, the Higgs boson width at the Large Hadron Collider through "interferometry." We investigate how the shift depends on the Higgs width, in a model that maintains constant Higgs boson signal yields. At Higgs widths above 30 MeV, the mass shift is over 200 MeV and increases with the square root of the width. The apparent mass shift could be measured by comparing with the ZZ^{*} channel, where the shift is much smaller. It might be possible to measure the shift more accurately by exploiting its strong dependence on the Higgs transverse momentum.

Dixon LJ; Li Y

2013-09-01

207

Nonlocal potentials and resonances of narrow width  

Energy Technology Data Exchange (ETDEWEB)

This paper discusses resonances of narrow width in the context of bound states embedded in the continuum spectrum of nonlocal potentials. Feshbach's theory of nuclear reactions leads directly to resonance theory, and we base our discussion here on the techniques he developed for shifting nuclear many-body aspects into effective single-particle nonlocal potentials. In our formulation, the many-body state of the compound nucleus is represented by a single-particle state. The basis for our discussion is a two channel model of a resonance of zero width, with a continuum bound state originating from the coupling of a bound state to the single-particle scattering state. We give a specific example of a model which leads to an arbitrarily narrow (nonzero width) resonance, and demonstrate that the width of the resonance produced by breaking the continuum bound state is proportional to (..lambda..-1)/sup 2/, where the parameter ..lambda.. is such that ..lambda.. = 1 corresponds to the condition necessary for the existence of a continuum bound state.

Bagchi, B.; Mulligan, B.; Seyler, R.G.

1982-07-01

208

Bounding the Higgs Boson Width through Interferometry  

Science.gov (United States)

We study the change in the diphoton-invariant-mass distribution for Higgs boson decays to two photons, due to interference between the Higgs resonance in gluon fusion and the continuum background amplitude for gg???. Previously, the apparent Higgs mass was found to shift by around 100 MeV in the standard model in the leading-order approximation, which may potentially be experimentally observable. We compute the next-to-leading-order QCD corrections to the apparent mass shift, which reduce it by about 40%. The apparent mass shift may provide a way to measure, or at least bound, the Higgs boson width at the Large Hadron Collider through “interferometry.” We investigate how the shift depends on the Higgs width, in a model that maintains constant Higgs boson signal yields. At Higgs widths above 30 MeV, the mass shift is over 200 MeV and increases with the square root of the width. The apparent mass shift could be measured by comparing with the ZZ* channel, where the shift is much smaller. It might be possible to measure the shift more accurately by exploiting its strong dependence on the Higgs transverse momentum.

Dixon, Lance J.; Li, Ye

2013-09-01

209

Rank-width and Tree-width of H-minor-free Graphs  

CERN Multimedia

We prove that for any fixed r>=2, the tree-width of graphs not containing K_r as a topological minor (resp. as a subgraph) is bounded by a linear (resp. polynomial) function of their rank-width. We also present refinements of our bounds for other graph classes such as K_r-minor free graphs and graphs of bounded genus.

Fomin, Fedor V; Thilikos, Dimitrios M

2009-01-01

210

The ratio of the interzygomatic width with mesiodistal width of maxillary anterior teeth  

Directory of Open Access Journals (Sweden)

Full Text Available Esthetics is one of the prosthetic treatment goals. Correct selection of anterior teeth, regarding size and appearance, results in a successful treatment. The goal of the present research was to investigate the relationship between interzygomatic width and maxillary anterior teeth width in order to find a better determinant for artificial anterior teeth selection. In this study, the interzygomatic width and maxillary central incisors width and also the width of six maxillary anterior- teeth, in 71 subjects (29females and 42 males) were measured. The results showed a significant difference in maxillary anterior teeth width, comparing men and women, (P<0.05). These measurement in people under study, are less than Europeans. The interzygomatic width was also more in men than women (PO.05), which is, less than of European race. The ratio between interzygomatic and central maxillary incisor width was 15:1 which is less than 16:1 that is used in clinic. Thus, it is recommended to pay more attention to anterior teeth selection, especially in young patients.

Savabi O;  Ghasabzadeh M

2002-01-01

211

Escape- and spreading width of the isobaric analog state  

Energy Technology Data Exchange (ETDEWEB)

Data and systematics on the natural line width, the escape width, and the spreading width of ground state isobaric analog states are presented. The relation between isospin impurity and spreading width, and between escape width and neutron spectroscopic factors is discussed. The neutron decay, possible only through isospin breaking, was measured directly and is found to have a mostly statistical spectral shape.

Vanderwerf, S.Y.

1991-01-01

212

Equivalences of monoidal model categories  

CERN Multimedia

We construct Quillen equivalences between the model categories of monoids (rings), modules and algebras over two Quillen equivalent model categories under certain conditions. This is a continuation of our earlier work in "Algebras and modules in monoidal model categories" where we established model categories of monoids, modules and algebras. As an application we extend the Dold-Kan equivalence to show that the model categories of simplicial rings, modules and algebras are Quillen equivalent to the associated model categories of connected differential graded rings, modules and algebras. We also show that our classification results in "Stable model categories are categories of modules" translate to any one of the known symmetric monoidal model categories of spectra.

Schwede, S; Schwede, Stefan; Shipley, Brooke

2002-01-01

213

Tissue Engineered Human Skin Equivalents  

Directory of Open Access Journals (Sweden)

Full Text Available Human skin not only serves as an important barrier against the penetration of exogenous substances into the body, but also provides a potential avenue for the transport of functional active drugs/reagents/ingredients into the skin (topical delivery) and/or the body (transdermal delivery). In the past three decades, research and development in human skin equivalents have advanced in parallel with those in tissue engineering and regenerative medicine. The human skin equivalents are used commercially as clinical skin substitutes and as models for permeation and toxicity screening. Several academic laboratories have developed their own human skin equivalent models and applied these models for studying skin permeation, corrosivity and irritation, compound toxicity, biochemistry, metabolism and cellular pharmacology. Various aspects of the state of the art of human skin equivalents are reviewed and discussed.

Zheng Zhang; Bozena B. Michniak-Kohn

2012-01-01

214

Principle of equivalence and electromagnetism  

Energy Technology Data Exchange (ETDEWEB)

It is shown that the local expression for the electrostatic potential of a point charge suggested from the equivalence principle is different from the one resulting from the global consideration in the Schwarzschild space-time.

Leaute, B.; Linet, B. (Paris-6 Univ., 75 (France). Inst. Henri Poincare)

1983-01-01

215

Equivalence of OLAP Dimension Schemas  

UK PubMed Central (United Kingdom)

Dimension schemas are abstract models of the data hierarchiesthat populate OLAP warehouses. Although there is abundant workon schema equivalence in a variety of data models, these works do notcover dimension schemas. In this paper we propose a notion of equivalencethat allows to compare dimension schemas with respect to theirinformation capacity. The proposed notion is intended to capture dimensionschema equivalence in the context of OLAP schema restructuring.

Carlos A. Hurtado; Claudio Gutierrez

216

Equivalence principle and spatial curvature  

Energy Technology Data Exchange (ETDEWEB)

An examination is made of the connection between the equivalence principle of general relativity and the non-Euclidean properties of space. The arguments commonly advanced to suggest a necessary connection between these two features of general relativity are reviewed and critically discussed. It is shown that although gravitational time dilation is an immediate consequence of the equivalence principle the corresponding effects on space are not such immediate or logically necessary consequences of this principle.

Dugdale, D.E. (Keele Univ. (UK))

1981-01-01

217

Morita equivalence of nest algebras  

CERN Document Server

Let N_1 (resp.N_2) be a nest A (resp. B) be the corresponding nest algebra, A_0 (resp. B_0) be the subalgebra of compact operators. We prove that the nests N_1, N_2 are isomorphic if and only if the algebras A, B are weakly-* Morita equivalent if and only if the algebras A_0, B_0 are strongly Morita equivalent. We characterize the nest isomorphisms which implement stable isomorphism between the corresponding nest algebras.

Eleftherakis, G K

2010-01-01

218

Finite width effects in Higgs boson decays as a means of measuring massive particle widths  

International Nuclear Information System (INIS)

[en] We calculate decays of a standard model Higgs boson via a virtual massive particle and discuss how this depends on the massive particle total width. If the partial width for a Higgs boson to decay via a virtual massive particle can be measured, this gives a measurement of that massive particle close-quote s width. We discuss how one would go about measuring these partial widths of a Higgs boson experimentally, and how this could lead to a measurement of the W boson and t quark widths. For the latter, extreme dependence on the Higgs boson mass and the small H?tt* branching ratios mean that little can be learned about the t quark width. For the former there is also a larger dependence on the Higgs boson mass; however, this can be removed by taking the ratio of H?WW* decays to H?ZZ* decays. This ratio also has the advantage of being fairly insensitive to physics beyond the standard model. Unfortunately, for Higgs boson masses of interest the H?ZZ* branching ratio is small enough that we require many thousands of tagged Higgs boson decays before an accurate measurement of the W width can be made. This is likely to be hard experimentally. copyright 1996 The American Physical Society

1996-01-01

219

Semileptonic width ratios among beauty hadrons  

CERN Multimedia

We present predictions based on the heavy quark expansion in QCD. We find SU(3) breaking in B mesons suppressed in the framework of the HQE. B_s is expected to have the semileptonic width about 1% lower and Lambda_b about 3% higher when compared to Gamma_{sl}(B_d). The largest partial-rate preasymptotic effect is Pauli interference in the b-->u ell nu channel in Lambda_b, about +10%. We point out that the Omega_b semileptonic width is expected not to exceed that of B_d and may turn out to be the smallest among stable b hadrons despite the large mass. The underlying differences with phase-space models are briefly addressed through the heavy mass expansion.

Bigi, I I; Uraltsev, N

2011-01-01

220

Decay widths in the massive Schwinger model  

CERN Document Server

By a closer inspection of the massive Schwinger model within mass perturbation theory we find that, in addition to the $n$-boson bound states, a further type of hybrid bound states has to be included into the model. Further we explicitly compute the decay widths of the three-boson bound state and of the lightest hybrid bound state. By a closer inspection of the massive Schwinger model within mass perturbation theory we find that, in addition to the $n$-boson bound states, a further type of hybrid bound states has to be included into the model. Further we explicitly compute the decay widths of the three-boson bound state and of the lightest hybrid bound state.

Adam, C

1997-01-01

 
 
 
 
221

Power flux widths in the ASDEX divertor  

Energy Technology Data Exchange (ETDEWEB)

The reciprocating Langmuir probe on ASDEX is located in the upper outer divertor and is capable of delivering a maximum of four radial profiles of plasma parameters during a discharge. The power flux profiles allow a direct evaluation of the effective power channel width which apart from offering a direct estimate of target plate power loading, it is also fundamental in understanding SOL transport processes. The evolution of power flux profiles and systematic trends of the corresponding widths for ohmically and NI heated discharges are presented for parametric scans in n{sub e}, I{sub p}, B{sub t} and injected neutral power. Langmuir probe data are compared and correlated with data from the Lithium beam probe which delivers density profiles in the outer midplane and the YAG Thomson scattering system which yields density and temperature near the separatrix at the lower plasma. (author) 6 refs., 4 figs.

Kyriakakis, G.; Kakoulidis, E.; Tsois, N. [National Research Centre for the Physical Sciences Democritos, Athens (Greece); McCormick, K.; Neuhauser, J. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

1992-12-31

222

Matroid 3-connectivity and branch width  

CERN Document Server

We prove that, for each nonnegative integer k and each matroid N, if M is a 3-connected matroid containing N as a minor, and the the branch width of M is sufficiently large, then there is a k-element subset X of E(M) such that one of M\\X and M/X is 3-connected and contains N as a minor.

Geelen, Jim

2011-01-01

223

Continuum RPA calculation of escape widths  

Energy Technology Data Exchange (ETDEWEB)

Particle-hole partial decay widths are calculated within the continuum RPA exactly, i.e. without any further approximation, in a square well plus Coulomb potential and using a separable residual interaction. The results are compared with the ones obtained by making pole expansions of the single-particle Green functions (Berggren and Mittag-Leffler). It is found that the Berggren and Mittag-Leffler expansions give results in good agreement with the 'exact' ones. (orig.).

Vertse, T. (Inst. of Nuclear Research, Hungarian Academy of Sciences, Debrecen (Hungary)); Curutchet, P.; Liotta, R.J. (Manne Siegbahn Inst. of Physics, Stockholm (Sweden)); Bang, J. (Niels Bohr Inst., Copenhagen (Denmark)); Giai, N. van (Inst. de Physique Nucleaire, 91 - Orsay (France))

1991-07-25

224

Continuum RPA calculation of escape widths  

International Nuclear Information System (INIS)

[en] Particle-hole partial decay widths are calculated within the continuum RPA exactly, i.e. without any further approximation, in a square well plus Coulomb potential and using a separable residual interaction. The results are compared with the ones obtained by making pole expansions of the single-particle Green functions (Berggren and Mittag-Leffler). It is found that the Berggren and Mittag-Leffler expansions give results in good agreement with the 'exact' ones. (orig.)

1991-07-25

225

Biologic Width - The No Encroachment Zone  

Directory of Open Access Journals (Sweden)

Full Text Available Dentistry of modern era is dominated by restorative procedures which are carried out to meet the demands of not only function but also esthetics. The dentist is having a narrow room of flexibility to wander in order to achieve a good esthetic restoration which is fully functional, the design of preparation and the technique sensitive fabrication form one side of the coin and establishing a harmonious margin for a crown on abutment forms the other side of the coin when trying to insert a fixed prosthetic restoration for replacing missing teeth, the phenomenon of biologic width was less understood till very recently but the growing clinical experience and better diagnostic skills of today has helped us to understand the intricacies of this concept and the need for its maintenance, the violation of which leads to the ultimate failure of the prosthesis. This article attempts to explain the ways of diagnosing biologic width violation, the care needed to exert when preparing a teeth to receive a crown and exactly deciding where to place the margins of the crown to avoid biologic width violation

Hari Krishna Reddy S; Chetan Kumar S

2010-01-01

226

Are there any good digraph width measures?  

CERN Document Server

Several different measures for digraph width have appeared in the last few years. However, none of them shares all the "nice" properties of treewidth: First, being \\emph{algorithmically useful} i.e. admitting polynomial-time algorithms for all $\\MS1$-definable problems on digraphs of bounded width. And, second, having nice \\emph{structural properties} i.e. being monotone under taking subdigraphs and some form of arc contractions. As for the former, (undirected) $\\MS1$ seems to be the least common denominator of all reasonably expressive logical languages on digraphs that can speak about the edge/arc relation on the vertex set.The latter property is a necessary condition for a width measure to be characterizable by some version of the cops-and-robber game characterizing the ordinary treewidth. Our main result is that \\emph{any reasonable} algorithmically useful and structurally nice digraph measure cannot be substantially different from the treewidth of the underlying undirected graph. Moreover, we introduce \\...

Ganian, Robert; Kneis, Joachim; Meister, Daniel; Obdržálek, Jan; Rossmanith, Peter; Sikdar, Somnath

2010-01-01

227

Width and partial widths of unstable particles in the light of the Nielsen identities  

International Nuclear Information System (INIS)

Fundamental properties of unstable particles, including mass, width, and partial widths, are examined on the basis of the Nielsen identities (NI) that describe the gauge dependence of Green functions. In particular, we prove that the pole residues and associated definitions of branching ratios and partial widths are gauge independent to all orders. A simpler, previously discussed definition of branching ratios and partial widths is found to be gauge independent through next-to-next-to-leading order. It is then explained how it may be modified in order to extend the gauge independence to all orders. We also show that the physical scattering amplitude is the most general combination of self-energy, vertex, and box contributions that is gauge independent for arbitrary s, discuss the analytical properties of the NI functions, and exhibit explicitly their one-loop expressions in the Z-? sector of the standard model.

2002-04-15

228

The binding characteristics of a human bladder recombinant P2X purinoceptor, labelled with [3H]-alpha beta meATP, [35S]-ATP gamma S or [33P]-ATP.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

1. The binding of [3H]-alpha beta meATP, [35s]-ATP gamma S and [alpha 33P]-ATP to a human bladder P2X purinoceptor, transiently expressed in CHO-K1 cells using the Semliki Forest Virus (SFV) expression system, was examined. The characteristics of the binding sites were compared with results obtained...

Michel, A. D.; Lundström, K.; Buell, G. N.; Surprenant, A.; Valera, S.; Humphrey, P. P.

229

Spiral inflow feeding the nuclear starburst in M83, observed in H-alpha emission with the GHAFAS Fabry-Perot interferometer  

CERN Multimedia

We present observations of the nearby barred starburst galaxy, M83 (NGC5236), with the new Fabry-Perot interferometer GHAFAS mounted on the 4.2 meter William Herschel Telescope on La Palma. The unprecedented high resolution observations, of 16 pc/FWHM, of the H-alpha-emitting gas cover the central two kpc of the galaxy. The velocity field displays the dominant disk rotation with signatures of gas inflow from kpc scales down to the nuclear regions. At the inner Inner Lindblad Resonance radius of the main bar and centerd at the dynamical center of the main galaxy disk, a nuclear $5.5 (\\pm 0.9) \\times 10^8 M_\\odot$ rapidly rotating disk with scale length of $60 \\pm 20$ pc has formed. The nuclear starburst is found in the vicinity as well as inside this nuclear disk, and our observations confirm that gas spirals in from the outer parts to feed the nuclear starburst, giving rise to several star formation events at different epochs, within the central 100 pc radius of M83.

Fathi, Kambiz; Lundgren, Andreas A; Carignan, Claude; Hernandez, Olivier; Amram, Philippe; Balard, Philippe; Boulesteix, Jacques; Gach, Jean-Luc; Knapen, Johan H; Relaño, Monica

2007-01-01

230

A Survey of Local Group Galaxies Currently Forming Stars: III. A Search for Luminous Blue Variables and Other H-alpha Emission-Lined Stars  

CERN Multimedia

We describe a search for H-alpha emission-lined stars in M31, M33, and seven dwarfs in or near the Local Group (IC 10, NGC 6822, WLM, Sextans B, Sextans A, Pegasus and the Phoenix dwarf) using interference filter imaging with the KPNO and CTIO 4-m telescope and Mosaic cameras. The survey is aimed primarily at identifying new Luminous Blue Variables (LBVs) from their spectroscopic similarity to known LBVs, avoiding the bias towards photometric variability, which may require centuries to manifest itself if LBVs go through long quiescent periods. Followup spectroscopy with WIYN confirms that our survey detected a wealth of stars whose spectra are similar to the known LBVs. We "classify" the spectra of known LBVs, and compare these to the spectra of the new LBV candidates. We demonstrate spectacular spectral variability for several of the new LBV candidates, such as AM2, previously classified as a Wolf-Rayet star, which now shows FeI, FeII and Balmer emission lines but neither the NIII 4634,42 nor HeII 4686 emiss...

Massey, Philip; Olsen, K A G; Hodge, Paul W; Blaha, Cynthia; Jacoby, George H; Smith, R C; Strong, Shay B

2007-01-01

231

Determination of dihedral Psi angles in large proteins by combining NH(N)/C(alpha)H(alpha) dipole/dipole cross-correlation and chemical shifts.  

Science.gov (United States)

We propose a strategy based on the combination of experimental NH(N)/C(alpha)H(alpha) dipole/dipole cross-correlated relaxation rates and chemical shift analysis for the determination of Psi torsion angles in proteins. The method allows the determination of a dihedral angle that is not easily accessible by nuclear magnetic resonance (NMR). The measurement of dihedral angle restraints can be used for structure calculation, which is known to improve the quality of NMR structures. The method is of particular interest in the case of large proteins, for which spectral assignment of the nuclear Overhauser effect spectra, and therefore straightforward structural determination, is out of reach. One advantage of the method is that it is reasonably simple to implement, and could be used in association with other methods aiming at obtaining structural information on complex systems, such as residual dipolar coupling measurements. An illustrative example is analyzed in the case of the 30-kDa protein 6-phosphogluconolactonase. PMID:16786593

Loth, Karine; Abergel, Daniel; Pelupessy, Philippe; Delarue, Marc; Lopes, Philippe; Ouazzani, Jamal; Duclert-Savatier, Nathalie; Nilges, Michael; Bodenhausen, Geoffrey; Stoven, Véronique

2006-09-01

232

Dust Obscuration and Metallicity at High Redshift: New Inferences from UV, H-alpha, and 8 Micron Observations of z~2 Star-Forming Galaxies  

CERN Document Server

We use a sample of 90 spectroscopically-confirmed Lyman Break Galaxies with H-alpha and 24 micron observations to constrain the relationship between rest-frame 8 micron luminosity, L(8), and star formation rate (SFR) for L* galaxies at z~2. We find a tight correlation with 0.24 dex scatter between L8 and L(Ha)/SFR for z~2 galaxies with L(IR)~10^10 - 10^12 Lsun. Employing this relationship with a larger sample of 392 galaxies with spectroscopic redshifts, we find that the UV slope can be used to recover the dust attenuation of the vast majority of L* galaxies at z~2 to within 0.4 dex scatter using the local correlation. Separately, young galaxies with ages <100 Myr appear to follow an extinction curve that is steeper than the one found for local starburst galaxies. Therefore, such young galaxies may be significantly less dusty than inferred previously. Our results provide the first direct evidence, independent of the UV slope, for a correlation between UV and bolometric luminosity at high redshift, in the s...

Reddy, Naveen A; Pettini, Max; Steidel, Charles C; Shapley, Alice E

2010-01-01

233

EQUIVALENCE VERSUS NON-EQUIVALENCE IN ECONOMIC TRANSLATION  

Directory of Open Access Journals (Sweden)

Full Text Available This paper aims at highlighting the fact that “equivalence” represents a concept worth revisiting and detailing upon when tackling the translation process of economic texts both from English into Romanian and from Romanian into English. Far from being exhaustive, our analysis will focus upon the problems arising from the lack of equivalence at the word level. Consequently, relevant examples from the economic field will be provided to account for the following types of non-equivalence at word level: culturespecific concepts; the source language concept is not lexicalised in the target language; the source language word is semantically complex; differences in physical and interpersonal perspective; differences in expressive meaning; differences in form; differences in frequency and purpose of using specific forms and the use of loan words in the source text. Likewise, we shall illustrate a number of translation strategies necessary to deal with the afore-mentioned cases of non-equivalence: translation by a more general word (superordinate); translation by a more neutral/less expressive word; translation by cultural substitution; translation using a loan word or loan word plus explanation; translation by paraphrase using a related word; translation by paraphrase using unrelated words; translation by omission and translation by illustration.

Cristina, Chifane

2012-01-01

234

Phase-equivalent complex potentials  

International Nuclear Information System (INIS)

[en] Potentials providing the same complex phase shifts as a given complex potential but with a shallower real part are constructed with supersymmetric transformations. Successive transformations eliminate normalizable solutions corresponding to complex eigenvalues of the Schroedinger equation with the full complex potential. Two numerical techniques, finite differences and Lagrange meshes, are applied to the determination of these normalizable solutions. With respect to real potentials, a new feature is the occurrence of normalizable solutions with complex energies presenting a positive real part. Such solutions can be removed but may lead to complicated equivalent potentials with little physical interest. The derivation of equivalent potentials is tested on complex Poeschl-Teller potentials for which analytical solutions are available. As a physical application, a deep optical potential for the ?+16O scattering is transformed into an l-dependent equivalent shallow optical potential. (orig.)

1996-03-25

235

Pooling batches in drug stability study by using constant-width simultaneous confidence bands.  

UK PubMed Central (United Kingdom)

One important study objective in drug stability studies is to estimate the shelf-life of a drug. A key statistical problem involved in this is how to assess the practical equivalence of different batches of the same drug so that different batches can be subgrouped to produce a single shelf-life for the drug. In this paper constant-width simultaneous confidence bands are proposed to quantify the magnitude of difference between different batches, with a particular view to establish the practical equivalence of different batches. This approach is suitable for the situation that the intercepts and slopes of the regression lines for the batches cannot be assumed to be equal. It is shown how constant-width simultaneous confidence bands can be easily constructed for the multiple comparison of several general linear regression models. In particular, it is shown that constant-width simultaneous confidence bands have a better chance to establish the equivalence than, and so are preferable to, the hyperbola-shaped simultaneous confidence bands considered.

Liu W; Jamshidian M; Zhang Y; Bretz F; Han XL

2007-06-01

236

Pooling batches in drug stability study by using constant-width simultaneous confidence bands.  

Science.gov (United States)

One important study objective in drug stability studies is to estimate the shelf-life of a drug. A key statistical problem involved in this is how to assess the practical equivalence of different batches of the same drug so that different batches can be subgrouped to produce a single shelf-life for the drug. In this paper constant-width simultaneous confidence bands are proposed to quantify the magnitude of difference between different batches, with a particular view to establish the practical equivalence of different batches. This approach is suitable for the situation that the intercepts and slopes of the regression lines for the batches cannot be assumed to be equal. It is shown how constant-width simultaneous confidence bands can be easily constructed for the multiple comparison of several general linear regression models. In particular, it is shown that constant-width simultaneous confidence bands have a better chance to establish the equivalence than, and so are preferable to, the hyperbola-shaped simultaneous confidence bands considered. PMID:17133619

Liu, W; Jamshidian, M; Zhang, Y; Bretz, F; Han, X L

2007-06-30

237

Width of the charge distribution in fission  

International Nuclear Information System (INIS)

The width of the charge distribution (for a fixed mass split) observed in nuclear fission can be estimated by assuming that it is associated with fluctuations in the collective coordinate corresponding to the flow of neutrons and protons back and forth through the neck connecting the nascent fragments. The possibility that different dynamical trajectories (one-body and viscous damping) can be distinguished is investigated for fission of 236U. It is found that, although the predicted charge dispersion is quite close to the observed value, the curves for the two trajectories are so close that a choice between the trajectories cannot be made. 2 figures

1981-01-01

238

Effect of different Gaussian width on disappearance of flow  

CERN Multimedia

In the present paper, we reduce and enhance the scaled Gaussian width(SGW) by 30% from the normal SGW of the systems and see its effect on balance energy. The scaled Gaussian width can be defined as the ratio of Gaussian width used for any nuclei to the Gaussian width used for Au nuclei(i.e. 8.66 $fm^2$).

Rajni,

2011-01-01

239

Pulse width modulation inverter with battery charger  

Energy Technology Data Exchange (ETDEWEB)

An inverter is connected between a source of DC power and a three-phase AC induction motor, and a microprocessor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .theta., where .theta. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands for electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a "flyback" DC-DC converter circuit for recharging the battery.

Slicker, James M. (Union Lake, MI)

1985-01-01

240

Equivalence classes for gauge theories  

CERN Document Server

In this paper we go deep into the connection between duality and fields redefinition for general bilinear models involving the 1-form gauge field $A$. A duality operator is fixed based on "gauge embedding" procedure. Dual models are shown to fit in equivalence classes of models with same fields redefinitions.

Gomes, M A M

2005-01-01

 
 
 
 
241

Equivalence classes for gauge theories  

Energy Technology Data Exchange (ETDEWEB)

In this paper we go deep into the connection between duality and fields redefinition for general bilinear models involving the 1-form gauge field A. A duality operator is fixed based on a 'gauge embedding' procedure. Dual models are shown to fit in equivalence classes of models with the same fields re-definitions. (authors)

Gomes, M.A.M.; Landim, R.R. [Universidade Federal do Ceara, Dept. de Fisica, Ceara (Brazil)

2005-06-01

242

Optimal testing of equivalence hypotheses  

CERN Multimedia

In this paper we consider the construction of optimal tests of equivalence hypotheses. Specifically, assume X_1,..., X_n are i.i.d. with distribution P_{\\theta}, with \\theta \\in R^k. Let g(\\theta) be some real-valued parameter of interest. The null hypothesis asserts g(\\theta)\

Romano, J P

2005-01-01

243

Equivalences of Higher Derived Brackets  

CERN Document Server

This note elaborates on Th. Voronov's construction [math/0304038,math/0412202] of $L_\\infty$-structures via higher derived brackets with a Maurer-Cartan element. It is shown that gauge equivalent Maurer-Cartan elements induce $L_\\infty$-isomorphic structures. Applications in symplectic, Poisson and Dirac geometry are discussed.

Cattaneo, Alberto S

2007-01-01

244

On Fractional Programming and Equivalence.  

Science.gov (United States)

Under fairly general conditions, a nonlinear fractional program, where the function to be maximized has the form f(x)/g(x), is shown to be equivalent to a nonlinear program not involving fractions. The latter program is not generally a convex program, but...

B. D. Craven B. Mond

1975-01-01

245

Quantum Equivalent Magnetic Fields that Are Not Classically Equivalent  

CERN Multimedia

We construct pairs of compact K\\"ahler-Einstein manifolds $(M_i,g_i,\\omega_i)$ ($i=1,2)$ of complex dimension $n$ with the following properties: The canonical line bundle $L_i=\\bigwedge^n T^*M_i$ has Chern class $[\\omega_i/2\\pi]$, and for each integer $k$ the tensor powers $L_1^{\\otimes k}$ and $L_2^{\\otimes k}$ are isospectral for the bundle Laplacian associated with the canonical connection, while $M_1$ and $M_2$ -- and hence $T^*M_1$ and $T^*M_2$ -- are not homeomorphic. In the context of geometric quantization, we interpret these examples as magnetic fields which are quantum equivalent but not classically equivalent. Moreover, we construct many examples of line bundles $L$, pairs of potentials $Q_1$, $Q_2$ on the base manifold, and pairs of connections $\

Gordon, Carolyn; Schueth, Dorothee; Webb, David

2010-01-01

246

Direct measurement of the W boson width.  

Science.gov (United States)

We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W --> enu candidate events. Data from approximately 1 fb(-1) of integrated luminosity recorded at square root of s = 1.96 TeV by the D0 detector at the Fermilab Tevatron pp collider are analyzed. We use the same methods and data sample that were used for our recently published W boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, 2.028 +/- 0.072 GeV, is in agreement with the predictions of the standard model. PMID:20366142

Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Ancu, L S; Andeen, T; Anzelc, M S; Aoki, M; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Atramentov, O; Avila, C; BackusMayes, J; Badaud, F; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Blazey, G; Blessing, S; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Bu, X B; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burnett, T H; Buszello, C P; Calfayan, P; Calpas, B; Calvet, S; Cammin, J; Carrasco-Lizarraga, M A; Carrera, E; Carvalho, W; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Cheu, E; Cho, D K; Cho, S W; Choi, S; Choudhary, B; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Cutts, D; Cwiok, M; Das, A; Davies, G; De, K; de Jong, S J; De La Cruz-Burelo, E; DeVaughan, K; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dorland, T; Dubey, A; Dudko, L V; Duflot, L; Duggan, D; Duperrin, A; Dutt, S; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Escalier, M; Evans, H; Evdokimov, A; Evdokimov, V N; Facini, G; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fuess, S; Gadfort, T; Galea, C F; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Geng, W; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Golovanov, G; Gómez, B; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Harder, K; Harel, A; Hauptman, J M; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinson, A P; Heintz, U; Hensel, C; Heredia-De La Cruz, I; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Huske, N; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jamin, D; Jesik, R; Johns, K; Johnson, C; Johnson, M; Johnston, D; Jonckheere, A; Jonsson, P; Juste, A; Kajfasz, E; Karmanov, D; Kasper, P A; Katsanos, I; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Khatidze, D; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Kozelov, A V; Kraus, J; Kuhl, T; Kumar, A; Kupco, A; Kurca, T; Kuzmin, V A; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lebrun, P; Lee, H S; Lee, W M; Leflat, A; Lellouch, J; Li, L; Li, Q Z; Lietti, S M; Lim, J K; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna-Garcia, R; Lyon, A L; Maciel, A K A; Mackin, D; Mättig, P; Magaña-Villalba, R; Mal, P K; Malik, S; Malyshev, V L; Maravin, Y; Martin, B; McCarthy, R; McGivern, C L; Meijer, M M; Melnitchouk, A; Mendoza, L; Menezes, D; Mercadante, P G; Merkin, M; Meyer, A; Meyer, J; Mondal, N K; Montgomery, H E; Moore, R W; Moulik, T; Muanza, G S; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nogima, H; Novaes, S F; Nunnemann, T; Obrant, G; Ochando, C; Onoprienko, D; Orduna, J; Oshima, N; Osman, N; Osta, J; Otec, R; Otero y Garzón, G J; Owen, M; Padilla, M; Padley, P; Pangilinan, M; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Penning, B; Perfilov, M; Peters, K; Peters, Y; Pétroff, P; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M-E; Polozov, P; Popov, A V; Prewitt, M; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rakitine, A; Rangel, M S; Ranjan, K; Ratoff, P N; Renkel, P; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Sanghi, B; Savage, G; Sawyer, L; Scanlon, T; Schaile, D; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schlobohm, S; Schwanenberger, C; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shivpuri, R K; Siccardi, V; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S

2009-12-04

247

Direct measurement of the W boson width  

Energy Technology Data Exchange (ETDEWEB)

We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W {yields} e{nu} candidates selected in 1 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron collider in p{bar p} collisions at {radical}s = 1.96 TeV. We use the same methods and data sample that were used for our recently published W boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, 2.028 {+-} 0.072 GeV, is in agreement with the predictions of the standard model and is the most precise direct measurement result from a single experiment to date.

Abazov, V.M.; /Dubna, JINR; Abbott, B.; /Oklahoma U.; Abolins, M.; /Michigan State U.; Acharya, B.S.; /Tata Inst.; Adams, M.; /Illinois U., Chicago; Adams, T.; /Florida State U.; Aguilo, E.; /Alberta U. /Simon Fraser U. /McGill U.; Ahsan, M.; /Kansas State U.; Alexeev, G.D.; /Dubna, JINR; Alkhazov, G.; /St. Petersburg, INP; Alton, A.; /Michigan U. /Northeastern U.

2009-09-01

248

First Digit Distribution of Hadron Full Width  

CERN Multimedia

A phenomenological law, called Benford's law, states that the occurrence of the first digit, i.e., $1,2,...,9$, of numbers from many real world sources is not uniformly distributed, but instead favors smaller ones according to a logarithmic distribution. We investigate, for the first time, the first digit distribution of the full widths of mesons and baryons in the well defined science domain of particle physics systematically, and find that they agree excellently with the Benford distribution. We also discuss several general properties of Benford's law, i.e., the law is scale-invariant, base-invariant, and power-invariant. This means that the lifetimes of hadrons follow also Benford's law.

Shao, Lijing; 10.1142/S0217732309031223

2010-01-01

249

First Digit Distribution of Hadron Full Width  

Science.gov (United States)

A phenomenological law, called Benford's law, states that the occurrence of the first digit, i.e. 1, 2,…, 9, of numbers from many real world sources is not uniformly distributed, but instead favors smaller ones according to a logarithmic distribution. We investigate, for the first time, the first digit distribution of the full widths of mesons and baryons in the well-defined science domain of particle physics systematically, and find that they agree excellently with the Benford distribution. We also discuss several general properties of Benford's law, i.e. the law is scale-invariant, base-invariant and power-invariant. This means that the lifetimes of hadrons also follow Benford's law.

Shao, Lijing; Ma, Bo-Qiang

250

Characterizing Width Uniformity by Wave Propagation  

CERN Multimedia

This work describes a novel image analysis approach to characterize the uniformity of objects in agglomerates by using the propagation of normal wavefronts. The problem of width uniformity is discussed and its importance for the characterization of composite structures normally found in physics and biology highlighted. The methodology involves identifying each cluster (i.e. connected component) of interest, which can correspond to objects or voids, and estimating the respective medial axes by using a recently proposed wavefront propagation approach, which is briefly reviewed. The distance values along such axes are identified and their mean and standard deviation values obtained. As illustrated with respect to synthetic and real objects (in vitro cultures of neuronal cells), the combined use of these two features provide a powerful description of the uniformity of the separation between the objects, presenting potential for several applications in material sciences and biology.

Costa, L F; Schubert, D; Costa, Luciano da F.; Mutinari, Giancarlo; Schubert, David

2003-01-01

251

Width lines of non hydrogenoid ions  

International Nuclear Information System (INIS)

An extensive theoretical and experimental work was carried out on the ns-np and np-nd line widths (w) of noble gases after ionization (n=n0+1, were n0 is the principal quantum number of the fundamental configuration). A high current 'pinch' discharge was used as source. Electron density and temperature were estimated to be Ne=2.65x1016 cm-3 and T=1.45x104K respectively. Calculations were based on a semi-empirical approximation and the matrix elements (or transition probabilities) were evaluated in different approximation. Comparing our measurements with those of other authors, a systematic tendency, with a dependence on atomic number Z and ionization energy of the higher level L, was established. Finally, it has been established that for Ne>1017 cm-3, w ? Ne?, where ?=5/6. (Author). 8 refs., 1 fig., 1 tab.

1990-01-01

252

Locally potentially equivalent Galois representations  

CERN Multimedia

We show that if two continuous semi-simple \\(\\ell \\)-adic Galois representations are locally potentially equivalent at a sufficiently large set of places then they are globaly potentially equivalent. We also prove an analogous result for arbitrarily varying powers of character values evaluated at the Frobenius conjugacy classes. In the context of modular forms, we prove: given two non-CM newforms $f$ and $g$ of weight at least two, such that $a_p(f)^{n_p}=a_p(g)^{n_p}$ on a set of primes of positive upper density and for some set of natural numbers $n_p$, then $f$ and $g$ are twists of each other by a Dirichlet character.

Patankar, Vijay M

2010-01-01

253

Equivalent circuit analysis of sled  

Energy Technology Data Exchange (ETDEWEB)

A direct application of equivalent circuit concepts leads to: (1) confirmation of Perry Wilson's SLED (SLAC Linac Energy Doubler) equation; (2) an equation that applies to a SLED device with input and output waveguides of different characteristic impedances; and (3) an equation that results if we demand that no power be lost by reflection from SLED. If the incident voltage is tailored as prescribed by this equation, the cavity voltage tracks the incident voltage and the reflected voltage is zero.

Lippmann, B.A.

1986-05-01

254

Equivalence of TBA and QTM  

CERN Multimedia

The traditional thermodynamic Bethe ansatz (TBA) equations for the XXZ model at $|\\Delta|\\ge 1$ are derived within the quantum transfer matrix (QTM) method. This provides further evidence of the equivalence of both methods. Most importantly, we derive an integral equation for the free energy formulated for just one unknown function. This integral equation is different in physical and mathematical aspects from the established ones. The single integral equation is analytically continued to the regime $|\\Delta|<1$.

Takahashi, M; Klümper, A; Takahashi, Minoru; Shiroishi, Masahiro; Klumper, Andreas

2001-01-01

255

Equivalence of TBA and QTM  

International Nuclear Information System (INIS)

[en] The traditional thermodynamic Bethe ansatz equations for the XXZ model at vertical bar ? vertical bar ? 1 are derived within the quantum transfer matrix method. This provides further evidence of the equivalence of both methods. Most importantly, we derive an integral equation for the free energy formulated for just one unknown function. This integral equation differs in physical and mathematical aspects to the established ones. The single integral equation is analytically continued to the regime vertical bar ? vertical bar

2001-04-06

256

Foxby equivalence over associative rings  

CERN Multimedia

We extend the definition of a semidualizing module to associative rings. This enables us to define and study Auslander and Bass classes with respect to a semidualizing bimodule C. We then study the classes of C-flats, C-projectives, and C-injectives, and use them to provide a characterization of the modules in the Auslander and Bass classes. We extend Foxby equivalence to this new setting. This paper contains a few results which are new in the commutative, noetherian setting.

Holm, H; Holm, Henrik; White, Diana

2006-01-01

257

Equivalent circuit analysis of sled  

International Nuclear Information System (INIS)

A direct application of equivalent circuit concepts leads to: (1) confirmation of Perry Wilson's SLED (SLAC Linac Energy Doubler) equation; (2) an equation that applies to a SLED device with input and output waveguides of different characteristic impedances; and (3) an equation that results if we demand that no power be lost by reflection from SLED. If the incident voltage is tailored as prescribed by this equation, the cavity voltage tracks the incident voltage and the reflected voltage is zero.

1986-01-01

258

Equivalent linearization of impacting structures  

International Nuclear Information System (INIS)

[en] Complex industrial structures are generally divided in several substructures. Even if the global behavior of the structure may by considered as linear, some substructures present local nonlinearities like impacts, sliding, or plasticity. To study the response of the whole structure the usual method consists of replacing the nonlinear substructures by linear models. The effect of the substructure is made equivalent to the nonlinear effect of the real substructure. Such equivalent models are called Linear Equivalent Models (LEM). This paper is mainly focused on the seismic behaviour of structures impacting on supports with gaps (for example pipes, steam generator etc...). Classical approaches to determine LEM consist generally in replacing the nonlinear support by a spring which stiffness is a function of the gap value and the excitation level. The limitations of such method will be identified in the case of a 1 degree of freedom (DOF) nonlinear oscillator. A new principle of LEM will be proposed and applied to this lDOF structure

1991-01-01

259

Equivalence of conservation laws and equivalence of potential systems  

CERN Multimedia

We study conservation laws and potential symmetries of (systems of) differential equations applying equivalence relations generated by point transformations between the equations. A Fokker-Planck equation and the Burgers equation are considered as examples. Using reducibility of them to the one-dimensional linear heat equation, we construct complete hierarchies of local and potential conservation laws for them and describe, in some sense, all their potential symmetries. Known results on the subject are interpreted in the proposed framework. This paper is an extended comment on the paper of J.-q. Mei and H.-q. Zhang [Internat. J. Theoret. Phys., 2006, in press].

Ivanova, N M; Ivanova, Nataliya M.; Popovych, Roman O.

2006-01-01

260

CCD photonic system for rail width measurement  

Science.gov (United States)

At present, in Moscow metro a track inspection vehicle, defectoscope and portable measurement instruments are used to measure the rail profile and the condition of track. The track inspection vehicle measures 8 parameters, such as rail height, width, lip flow, cant, gauge and rail identification. The main drawback of the existing track control devices is a contact mode of measurement that does not provide required accuracy during the movement of the track inspection vehicle. This drawback can be eliminated using the non-contact photonic system (NPS). NPS consists of four special digital CCD-cameras and four lasers (two cameras and two lasers on each rail), rigidly connected together and mounted underneath the rail inspection vehicle in such a manner that corners of vision and distances from the cameras up to the head of the rail remain fixed during the movement. A special processor is included at the output of each camera. It performs preliminary processing of the stripe image on the appropriate side of a rail and then codes (compresses) and transfers data to central computer. The central computer executes the rail profile restoration and its comparison with the pattern of the rail on the particular section of the track.

Ryabichenko, Roman B.; Popov, Sergey V.; Smoleva, Olga S.

1999-10-01

 
 
 
 
261

Absolute decay width measurements in 16O  

International Nuclear Information System (INIS)

The reaction 126C(63Li, d)168O* at a 6Li bombarding energy of 42 MeV has been used to populate excited states in 16O. The deuteron ejectiles were measured using the high-resolution Munich Q3D spectrograph. A large-acceptance silicon-strip detector array was used to register the recoil and break-up products. This complete kinematic set-up has enabled absolute ?-decay widths to be measured with high-resolution in the 13.9 to 15.9 MeV excitation energy regime in 16O; many for the first time. This energy region spans the 14.4 MeV four-? breakup threshold. Monte-Carlo simulations of the detector geometry and break-up processes yield detection efficiencies for the two dominant decay modes of 40% and 37% for the ?+12C(g.s.) and a+12C(2+1) break-up channels respectively.

2012-09-18

262

Formulae for partial widths derived from the Lindblad equation  

CERN Multimedia

A method for calculating partial widths of auto-ionizing states is proposed. It combines either a complex absorbing potential or exterior complex scaling with the Lindblad equation. The corresponding classical rate equations are reproduced, and the trace conservation inherent in the Lindblad equation ensures that the partial widths sums up to the total width of the initial auto-ionizing state.

Selstø, Sølve

2012-01-01

263

Changing step width alters lower extremity biomechanics during running.  

UK PubMed Central (United Kingdom)

Step width is a spatiotemporal parameter that may influence lower extremity biomechanics at the hip and knee joint. The purpose of this study was to determine the biomechanical response of the lower extremity joints to step width changes during running. Lower extremity data from 30 healthy runners, half of them male, were collected during running in three step width conditions: preferred, wide, and narrow. Dependent variables and step width were analyzed using a mixed model ANOVA and pairwise t-tests for post hoc comparisons. Step width was successfully altered in the wide and narrow conditions. Generally, frontal plane peak values decreased as step width increased from narrow to preferred to wide. Peak hip adduction and rearfoot eversion angles decreased as step width increased from narrow to wide. Peak knee abduction moment and knee abduction impulse also decreased as step width increased from narrow to wide. Although men and women ran differently, gender only influenced the effect of step width on peak rearfoot inversion moment. In conclusion, step width influences lower extremity biomechanics in healthy runners. When step width increased from narrow to wide, peak values of frontal plane variables decreased. In addition to previously reported changes at the rearfoot, the hip and knee joint biomechanics were also influenced by changes in step width.

Brindle RA; Milner CE; Zhang S; Fitzhugh EC

2013-07-01

264

GaO{sub 2}H, {alpha}-Ga{sub 2}O{sub 3} and {beta}-Ga{sub 2}O{sub 3} powders synthesized from ball-milled GaN powders  

Energy Technology Data Exchange (ETDEWEB)

GaO{sub 2}H, {alpha}-Ga{sub 2}O{sub 3} and {beta}-Ga{sub 2}O{sub 3} powders were synthesized from mechanically ground GaN powders with thermal annealing in a nitrogen atmosphere. The structural properties of GaO{sub 2}H, {alpha}-Ga{sub 2}O{sub 3} and {beta}-Ga{sub 2}O{sub 3} powders were investigated by X-ray powder diffraction (XRD), Fourier transform infrared (FT-IR) and scanning electron microscopy (SEM). The studies revealed that the samples obtained by ball-milled GaN for 4 h are orthorhombic crystalline GaO{sub 2}H phase. However, when GaO{sub 2}H were annealed in a nitrogen atmosphere at 550 and 950 deg. C, {alpha}-Ga{sub 2}O{sub 3} and {beta}-Ga{sub 2}O{sub 3} powders were obtained, respectively. SEM images indicated that the morphologies of GaO{sub 2}H, {alpha}-Ga{sub 2}O{sub 3} and {beta}-Ga{sub 2}O{sub 3} are ruleless, and their sizes are in the range of about 300-70, 150-70, and 150-70 nm, respectively.

Xiao Hongdi [School of Physics and Microelectronics, Shandong University, Jinan 250100 (China)]. E-mail: hdxiao@sdu.edu.cn; Ma Honglei [School of Physics and Microelectronics, Shandong University, Jinan 250100 (China)]. E-mail: hlma@sdu.edu.cn; Liang Wei [Jinan University, Jinan 250003 (China); Xue Chengshan [Institute of Semiconductor, Shandong Normal University, Jinan 250014 (China); Zhuang Huizhao [Institute of Semiconductor, Shandong Normal University, Jinan 250014 (China); Ma Jin [School of Physics and Microelectronics, Shandong University, Jinan 250100 (China); Hu Wenrong [School of Physics and Microelectronics, Shandong University, Jinan 250100 (China)

2005-12-15

265

Approximating the Minimum Equivalent Digraph  

CERN Multimedia

The MEG (minimum equivalent graph) problem is, given a directed graph, to find a small subset of the edges that maintains all reachability relations between nodes. The problem is NP-hard. This paper gives an approximation algorithm with performance guarantee of pi^2/6 ~ 1.64. The algorithm and its analysis are based on the simple idea of contracting long cycles. (This result is strengthened slightly in ``On strongly connected digraphs with bounded cycle length'' (1996).) The analysis applies directly to 2-Exchange, a simple ``local improvement'' algorithm, showing that its performance guarantee is 1.75.

Khuller, S; Young, N E; Khuller, Samir; Raghavachari, Balaji; Young, Neal E.

1995-01-01

266

Pulse widths effects on scintillator saturation  

International Nuclear Information System (INIS)

A test was performed over an extensive range of irrradiance (approximately five orders of magnitude) to see to what extent organic scintillators responded linearly with x-ray input. At the highest levels of irradiance achievable with the experimental configuration, but only for pulses in the region of 4.0 ns or wider, a degree of nonlinear response was observed for some of the scintillators. The data suggest that at levels below 1 mJ/cm2-ns it is safe to asume that for pulses 6.5 ns and shorter there is no significant level of nonlinearity to x rays with spectrum. For the cases of undoped NE111 and NE111 doped with 10 percent benzophenone, experimental conditions were such that it was possible to accumulate data significantly above the 1 mJ/cm2-ns level of irradiance. It is with these cases that a nonlinear response was observed. It is assumed that the same nonlinearity would have also been noticed had experimental conditions been such that equivalent levels of irradiance could have been achieved at the time the other samples were studied

1978-01-01

267

Global synchronization of parallel processors using clock pulse width modulation  

Energy Technology Data Exchange (ETDEWEB)

A circuit generates a global clock signal with a pulse width modification to synchronize processors in a parallel computing system. The circuit may include a hardware module and a clock splitter. The hardware module may generate a clock signal and performs a pulse width modification on the clock signal. The pulse width modification changes a pulse width within a clock period in the clock signal. The clock splitter may distribute the pulse width modified clock signal to a plurality of processors in the parallel computing system.

Chen, Dong; Ellavsky, Matthew R.; Franke, Ross L.; Gara, Alan; Gooding, Thomas M.; Haring, Rudolf A.; Jeanson, Mark J.; Kopcsay, Gerard V.; Liebsch, Thomas A.; Littrell, Daniel; Ohmacht, Martin; Reed, Don D.; Schenck, Brandon E.; Swetz, Richard A.

2013-04-02

268

Enhancement of heat transfer using varying width twisted tape inserts  

Directory of Open Access Journals (Sweden)

Full Text Available The present work shows the results obtained from experimental investigations of the augmentation of turbulent flow heat transfer in a horizontal tube by means of varying width twisted tape inserts with air as the working fluid. In order to reduce excessive pressure drops associated with full width twisted tape inserts, with less corresponding reduction in heat transfer coefficients, reduced width twisted tapes of widths ranging from 10 mm to 22 mm, which are lower than the tube inside diameter of 27.5 mm are used. Experiments were carried out for plain tube with/without twisted tape insert at constant wall heat flux and different mass flow rates. The twisted tapes are of three different twist ratios (3, 4 and 5) each with five different widths (26-full width, 22, 18, 14 and 10 mm) respectively. The Reynolds number varied from 6000 to 13500. Both heat transfer coefficient and pressure drop are calculated and the results are compared with those of plain tube. It was found that the enhancement of heat transfer with twisted tape inserts as compared to plain tube varied from 36 to 48% for full width (26mm) and 33 to 39% for reduced width (22 mm) inserts. Correlations are developed for friction factors and Nusselt numbers for a fully developed turbulent swirl flow, which are applicable to full width as well as reduced width twisted tapes, using a modified twist ratio as pitch to width ratio of the tape.

S. Naga Sarada; A.V. Sita Rama Raju; K. Kalyani Radha; L. Shyam Sunder

2010-01-01

269

Errors when shock waves interact due to numerical shock width  

Energy Technology Data Exchange (ETDEWEB)

A simple test problem proposed by Noh, a strong shock reflecting from a rigid wall, demonstrates a generic problem with numerical shock capturing algorithms at boundaries that Noh called ``excess wall heating.`` We show that the same type of numerical error occurs in general when shock waves interact. The underlying cause is the non-uniform convergence to the hyperbolic solution of the inviscid limit of the solution to the PDEs with viscosity. The error can be understood from an analysis of the asymptotic solution. For a propagating shock, there is a difference in the total energy of the parabolic wave relative to the hyperbolic shock. Moreover, the relative energy depends on the strength of the shock. The error when shock waves interact is due to the difference in the relative energies between the incoming and outgoing shock waves. It is analogous to a phase shift in a scattering matrix. A conservative differencing scheme correctly describes the Hugoniot jump conditions for a steady propagating shock. Therefore, the error from the asymptotics occurs in the transient when the waves interact. The entropy error that occurs in the interaction region remains localized but does not dissipate. A scaling argument shows that as the viscosity coefficient goes to zero, the error shrinks in spatial extend but is constant in magnitude. Noh`s problem of the reflection of a shock from a rigid wall is equivalent to the symmetric impact of two shock waves of the opposite family. The asymptotic argument shows that the same type of numerical error would occur when the shocks are of unequal strength. Thus, Noh`s problem is indicative of a numerical error that occurs when shocks interact due to the numerical shock width.

Menikoff, R.

1993-03-04

270

Errors when shock waves interact due to numerical shock width  

Energy Technology Data Exchange (ETDEWEB)

A simple test problem proposed by Noh, a strong shock reflecting from a rigid wall, demonstrates a generic problem with numerical shock capturing algorithms at boundaries that Noh called excess wall heating.'' We show that the same type of numerical error occurs in general when shock waves interact. The underlying cause is the non-uniform convergence to the hyperbolic solution of the inviscid limit of the solution to the PDEs with viscosity. The error can be understood from an analysis of the asymptotic solution. For a propagating shock, there is a difference in the total energy of the parabolic wave relative to the hyperbolic shock. Moreover, the relative energy depends on the strength of the shock. The error when shock waves interact is due to the difference in the relative energies between the incoming and outgoing shock waves. It is analogous to a phase shift in a scattering matrix. A conservative differencing scheme correctly describes the Hugoniot jump conditions for a steady propagating shock. Therefore, the error from the asymptotics occurs in the transient when the waves interact. The entropy error that occurs in the interaction region remains localized but does not dissipate. A scaling argument shows that as the viscosity coefficient goes to zero, the error shrinks in spatial extend but is constant in magnitude. Noh's problem of the reflection of a shock from a rigid wall is equivalent to the symmetric impact of two shock waves of the opposite family. The asymptotic argument shows that the same type of numerical error would occur when the shocks are of unequal strength. Thus, Noh's problem is indicative of a numerical error that occurs when shocks interact due to the numerical shock width.

Menikoff, R.

1993-03-04

271

Equivalent networks for SAW gratings.  

UK PubMed Central (United Kingdom)

An equivalent-network approach is described for the analysis of surface-acoustic-wave gratings. Circuit parameters can be theoretically determined by applying the finite-element method to an infinite array. In this approach, all of the effects of piezoelectric perturbation, mechanical perturbation, and energy storage are taken into account. To show the validity and usefulness of this approach, examples are computed for groove and metallic gratings. Both short and open circuited metallic gratings are treated. For grooves on isotropic and Y-Z LiNbO(3) substrates, the dependence of reflection characteristics on groove depth is investigated. For aluminum strips on X-112 degrees Y LiTaO(3) 34 degrees Y-X quartz, Y-Z LiNbO(3), and 128 degrees Y -X LiNbO(3) substrates, the dependence on metallization ratio is investigated in detail.

Koshiba M; Mitobe S

1988-01-01

272

From body burden to effective dose equivalent  

International Nuclear Information System (INIS)

The necessary data to calculate the effective committed dose equivalent and the effective dose-equivalent rate from measured body burdens are presented. Both ingestion and inhalation intakes are considered, for single intake as well as for continuous exposure.

1982-01-01

273

Power System Dynamic Equivalents Using Identification Techniques.  

Science.gov (United States)

This report describes the development and demonstration of an equivalent mathematical model for the representation of the external system dynamics at the boundary buses of an internal system. These equivalents are needed for different system studies in wh...

M. A. H. Ibrahim

1976-01-01

274

Pulse-width modulated external resistance increases the microbial fuel cell power output.  

Science.gov (United States)

This study describes MFC operation with a pulse-width modulated connection of the external resistor (R-PWM mode) at low and high frequencies. Analysis of the output voltage profiles acquired during R-PWM tests showed the presence of slow and fast dynamic components, which can be described by a simple equivalent circuit model suitable for process control applications. At operating frequencies above 100Hz a noticeable improvement in MFC performance was observed with the power output increase of 22-43% as compared to MFC operation with a constant external resistance. PMID:23989037

Coronado, J; Perrier, M; Tartakovsky, B

2013-08-09

275

Pulse-width modulated external resistance increases the microbial fuel cell power output.  

UK PubMed Central (United Kingdom)

This study describes MFC operation with a pulse-width modulated connection of the external resistor (R-PWM mode) at low and high frequencies. Analysis of the output voltage profiles acquired during R-PWM tests showed the presence of slow and fast dynamic components, which can be described by a simple equivalent circuit model suitable for process control applications. At operating frequencies above 100Hz a noticeable improvement in MFC performance was observed with the power output increase of 22-43% as compared to MFC operation with a constant external resistance.

Coronado J; Perrier M; Tartakovsky B

2013-11-01

276

CONCURRENT SUPERMASSIVE BLACK HOLE AND GALAXY GROWTH: LINKING ENVIRONMENT AND NUCLEAR ACTIVITY IN z = 2.23 H{alpha} EMITTERS  

Energy Technology Data Exchange (ETDEWEB)

We present results from a Almost-Equal-To 100 ks Chandra observation of the 2QZ Cluster 1004+00 structure at z = 2.23 (hereafter 2QZ Clus). 2QZ Clus was originally identified as an overdensity of four optically-selected QSOs at z = 2.23 within a 15 Multiplication-Sign 15 arcmin{sup 2} region. Narrow-band imaging in the near-IR (within the K band) revealed that the structure contains an additional overdensity of 22 z = 2.23 H{alpha}-emitting galaxies (HAEs), resulting in 23 unique z = 2.23 HAEs/QSOs (22 within the Chandra field of view). Our Chandra observations reveal that three HAEs in addition to the four QSOs harbor powerfully accreting supermassive black holes (SMBHs), with 2-10 keV luminosities of Almost-Equal-To (8-60) Multiplication-Sign 10{sup 43} erg s{sup -1} and X-ray spectral slopes consistent with unobscured active galactic nucleus (AGN). Using a large comparison sample of 210 z = 2.23 HAEs in the Chandra-COSMOS field (C-COSMOS), we find suggestive evidence that the AGN fraction increases with local HAE galaxy density. The 2QZ Clus HAEs reside in a moderately overdense environment (a factor of Almost-Equal-To 2 times over the field), and after excluding optically-selected QSOs, we find that the AGN fraction is a factor of Almost-Equal-To 3.5{sup +3.8}{sub -2.2} times higher than C-COSMOS HAEs in similar environments. Using stacking analyses of the Chandra data and Herschel SPIRE observations at 250 {mu}m, we respectively estimate mean SMBH accretion rates ( M-dot{sub BH}) and star formation rates (SFRs) for the 2QZ Clus and C-COSMOS samples. We find that the mean 2QZ Clus HAE stacked X-ray luminosity is QSO-like (L{sub 2-10{sub keV}} Almost-Equal-To [6-10] Multiplication-Sign 10{sup 43} erg s{sup -1}), and the implied M-dot{sub BH}/SFR Almost-Equal-To (1.6-3.2) Multiplication-Sign 10{sup -3} is broadly consistent with the local M{sub BH}/M{sub *} relation and z Almost-Equal-To 2 X-ray selected AGN. In contrast, the C-COSMOS HAEs are on average an order of magnitude less X-ray luminous and have M-dot{sub BH}/SFR Almost-Equal-To (0.2-0.4) Multiplication-Sign 10{sup -3}, somewhat lower than the local M{sub BH}/M{sub *} relation, but comparable to that found for z Almost-Equal-To 1-2 star-forming galaxies with similar mean X-ray luminosities. We estimate that a periodic QSO phase with duty cycle Almost-Equal-To 2%-8% would be sufficient to bring star-forming galaxies onto the local M{sub BH}/M{sub *} relation. This duty cycle is broadly consistent with the observed C-COSMOS HAE AGN fraction ( Almost-Equal-To 0.4%-2.3%) for powerful AGN with L{sub X} {approx}> 10{sup 44} erg s{sup -1}. Future observations of 2QZ Clus will be needed to identify key factors responsible for driving the mutual growth of the SMBHs and galaxies.

Lehmer, B. D.; Hornschemeier, A. E. [Department of Physics and Astronomy, Johns Hopkins University, Homewood Campus, Baltimore, MD 21218 (United States); Lucy, A. B. [NASA Goddard Space Flight Centre, Code 662, Greenbelt, MD 20771 (United States); Alexander, D. M.; Harrison, C. M.; Mullaney, J. R.; Swinbank, A. M. [Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Best, P. N. [SUPA, Institute for Astronomy, Royal Observatory of Edinburgh, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Geach, J. E. [Department of Physics, McGill University, 3600 rue University, Montreal, Quebec H3A 2T8 (Canada); Matsuda, Y. [Chile Observatory, National Astronomical Observatory of Japan, Tokyo 181-8588 (Japan); Smail, Ian [Institute for Computational Cosmology, Durham University, South Road, Durham DH1 3LE (United Kingdom); Sobral, D. [Leiden Observatory, Leiden University, P.O. Box 9513, NL-2300 RA Leiden (Netherlands)

2013-03-10

277

The Borel complexity of von Neumann equivalence  

CERN Document Server

We prove that for a countable group $\\Gamma$ containing a copy of the free group $\\F_n$, for some $2\\leq n\\leq\\infty$, as a normal subgroup, the equivalence relations of conjugacy, orbit equivalence and von Neumann equivalence of the ergodic a.e. free actions of $\\Gamma$ are analytic non-Borel equivalence relations in the Polish space of probability measure preserving $\\Gamma$ actions.

Epstein, Inessa

2011-01-01

278

Generalized heaps, inverse semigroups and Morita equivalence  

CERN Multimedia

Inverse semigroups are the abstract counterparts of pseudogroups of transformations. The abstract counterparts of atlases in differential geometry are what Wagner termed `generalized heaps'. These are sets equipped with a ternary operation satisfying certain axioms. We prove that there is a bijective correspondence between generalized heaps and the equivalence bimodules, defined by Steinberg. Such equivalence bimodules are used to define the Morita equivalence of inverse semigroups. This paper therefore shows that the Morita equivalence of inverse semigroups is determined by Wagner's generalized heaps.

Lawson, M V

2011-01-01

279

Relations among the radiative decay widths of charmonium states from superconvergent sum rules  

International Nuclear Information System (INIS)

[en] Relations among the decay widths for psi' ? chi/sub J/?, chi/sub J/ ? psi? (where chi/sub J/ is one of the 3P charmonium states) are derived from two Drell-Hearn--type sum rules. The relations, which make no use of the nonrelativistic cc-bar picture of the psi', chi, and psi states, predict ?'2:?'1:?'0 = 1.2:1.3:1.0, ?2:?1:?0 = 0.9:0.8:1.0, where ?'/sub J/ equivalent GAMMA (psi' ? chi/sub J/?)/(2J + 1) k/sub J/'3, ?/sub J/ equivalent GAMMA (chi/sub J/ ? psi?)/k/sub J//sup ts3/

1977-10-01

280

On geometrically equivalent S-acts  

CERN Document Server

In this paper, considering the geometric equivalence for algebras of a variety $_{S}A$ of S-acts over a monoid S, we obtain representation theorems describing all types of the equivalence classes of geometrically equivalent S-acts of varieties $_{S}A$ over groups S.

Katsov, Yefim

2011-01-01

 
 
 
 
281

Some spectral equivalences between Schrodinger operators  

CERN Multimedia

Spectral equivalences of the quasi-exactly solvable sectors of two classes of Schrodinger operators are established, using Gaudin-type Bethe ansatz equations. In some instances the results can be extended leading to full isospectrality. In this manner we obtain equivalences between PT-symmetric problems and Hermitian problems. We also find equivalences between some classes of Hermitian operators.

Dunning, C; Links, J

2008-01-01

282

Some spectral equivalences between Schroedinger operators  

International Nuclear Information System (INIS)

Spectral equivalences of the quasi-exactly solvable sectors of two classes of Schroedinger operators are established, using Gaudin-type Bethe ansatz equations. In some instances the results can be extended leading to full isospectrality. In this manner we obtain equivalences between PT-symmetric problems and Hermitian problems. We also find equivalences between some classes of Hermitian operators.

2008-08-08

283

An investigation of bridge width measurement and processing capabilities (1985)  

Energy Technology Data Exchange (ETDEWEB)

An investigation of Mound`s ability to measure and process bridges was conducted in 1985. Prior to improvements in the measuring system and technique, bridge width was found to have a sigma of 0.00019 in. After improvements were made, a sigma of 0.000047 was realized. Bridge length was found to be more erratic than width, although most of the inaccuracy was caused by measurement uncertainty. Length and width were found to have little or no correlation.

Armstrong, K.P. [comp.

1989-05-15

284

Stability-Guaranteed Width Control for Hot Strip Mill  

Science.gov (United States)

We propose a stability-guaranteed width control (SGWC) for the hot strip finishing mill. It is shown that the proposed SGWC guarantees the stability of the width controller by the universal approximation of the neural network. It is shown through the field test in the hot strip mill of POSCO that the stability of the width controller is guaranteed by the proposed control scheme.

Park, Cheol Jae; Hwang, I. Cheol

285

Violation of the gauge equivalence  

CERN Multimedia

F. V. Gubarev et al. (``On the significance of the vector potential squared'', Phys. Rev. Lett. 86, 2220) have argued that the minimum value of the volume integral of the vector potential squared may have physical meaning, in defiance of the gauge equivalence of potentials. Earlier, R. I. Khrapko proposed a gauge noninvariant electrodynamics spin tensor (``Spin density of electromagnetic waves'', [1]). The standard electrodynamics spin tensor is zero. Here we point out that the Biot-Savarat formula uniquely results in a preferred, "true" vector potential field which is generated from a given magnetic field. A similar integral formula uniquely permits to find a "true" scalar potential field generated from a given electric field even in the case of a nonpotential electric field. We say that an exterior derivative of a differential form is the boundary of this form and the integration of a form results in a new form named the generation. Generating from a generation yields zero. A boundary is closed. A generatio...

Khrapko, R I

2001-01-01

286

Sequential Decay Distortion of Goldhaber Model Widths for Spectator Fragments  

CERN Document Server

Momentum widths of the primary fragments and observed final fragments have been investigated within the framework of an Antisymmetrized Molecular Dynamics transport model code (AMD-V) with a sequential decay afterburner (GEMINI). It is found that the secondary evaporation effects cause the values of a reduced momentum width, $\\sigma_0$, derived from momentum widths of the final fragments to be significantly less than those appropriate to the primary fragment but close to those observed in many experiments. Therefore, a new interpretation for experiemental momentum widths of projectile-like fragments is presented.

Ma, Y G; Hagel, K; Murray, M; Ono, A; Wang, J S; Qin, L J; Makeev, A G; Smith, P; Natowitz, J B

2002-01-01

287

Asymptotic estimation of widths of the quasistationary states  

International Nuclear Information System (INIS)

The new integral formalism for the calculation of the width of the quasistationary states without using smallness of the barrier penetration factor is proposed. Asymptotic formula for the width of the short-living quasistationary states on the base of saddle-point approximation is derived. On the base of our approach the widths of ?-decay of the Pb isotopes, baryon resonances and dibaryon resonances were calculated. A good agreement of the theory and experiment was demonstrated. The natural explanation of the small widths of low lying dibaryon resonances was argued. (author). 23 refs., 1 fig., 4 tabs

1995-01-01

288

Distribution of resonance widths and dynamics of continuum coupling.  

UK PubMed Central (United Kingdom)

We analyze the statistics of resonance widths in a many-body Fermi system with open decay channels. Depending on the strength of continuum coupling, such a system reveals growing deviations from the standard chi-square (Porter-Thomas) width distribution. The deviations emerge from the process of increasing interaction of intrinsic states through common decay channels; in the limit of perfect coupling this process leads to the superradiance phase transition. The width distribution depends also on the intrinsic dynamics (chaotic versus regular). The results presented here are important for understanding the recent experimental data concerning the width distribution for neutron resonances in nuclei.

Celardo GL; Auerbach N; Izrailev FM; Zelevinsky VG

2011-01-01

289

Equivalent Simplification Method of Micro-Grid  

Directory of Open Access Journals (Sweden)

Full Text Available The paper concentrates on the equivalent simplification method for the micro-grid system connection into distributed network. The equivalent simplification method proposed for interaction study between micro-grid and distributed network. Micro-grid network, composite load, gas turbine synchronous generation, wind generation are equivalent simplification and parallel connect into the point of common coupling. A micro-grid system is built and three phase and single phase grounded faults are performed for the test of the equivalent model of micro-grid. The simulation results show that the equivalent model of micro-grid is effective, and the dynamic of equivalent model is similar with the detailed model of micro-grid. The equivalent simplification method for the micro-grid network and distributed components is suitable for the study of micro-grid.  

Cai Changchun; Cao Xiangqin

2013-01-01

290

Equivalence classes of permutations avoiding a pattern  

CERN Multimedia

Given a permutation pattern p and an equivalence relation on permutations, we study the corresponding equivalence classes all of whose members avoid p. Four relations are studied: Conjugacy, order isomorphism, Knuth-equivalence and toric equivalence. Each of these produces a known class of permutations or a known counting sequence. For example, involutions correspond to conjugacy, and permutations whose insertion tableau is hook-shaped with 2 in the first row correspond to Knuth-equivalence. These permutations are equinumerous with certain congruence classes of graph endomorphisms. In the case of toric equivalence we find a class of permutations that are counted by the Euler totient function, with a subclass counted by the number-of-divisors function. We also provide a new symmetry for bivincular patterns that produces some new non-trivial Wilf-equivalences

Ulfarsson, Henning

2010-01-01

291

The Local Lyman-$\\alpha$ Forest; 1, Distribution of HI Absorbers, Doppler Widths, and Baryon Content  

CERN Multimedia

In Paper I of this series (astro-ph/9911117) we described observations of 15 extragalactic targets taken with the Hubble Space Telescope GHRS/G160M grating for studies of the low-z Lya forest. We reported the detection of 110 Lya absorbers at significance level >3 sigma in the redshift range z=0.002-0.069, over a total pathlength of 116,000 km/s. In this second paper, we evaluate the physical properties of these Lya absorbers and compare them to their high-z counterparts. The distribution of Doppler parameters is similar to that at high redshift, with mean b = 35.0 +- 16.6 km/s. The true Doppler parameter may be somewhat lower, owing to component blends and non-thermal velocities. The distribution of equivalent widths exhibits a significant break at W~133mA, with an increasing number of weak absorbers (10mA-100mA). Adopting a curve of growth with b = 25 +- 5km/s and applying a sensitivity correction as a function of equivalent width and wavelength, we derive the distribution in column density, Nh^{-1.80+-0.05...

Penton, S V; Stocke, J T; Penton, Steven V.; Stocke, John T.

1999-01-01

292

Invisible width of the Z-boson and ``secret'' ?-? interactions  

Science.gov (United States)

The width of the decay Z-->???? in the presence of a possible nonstandard four-fermion ?-? interaction is calculated. From the invisible width of the Z-boson measured at LEP the upper bound on the strength F of such an effective interaction has been obtained: Fl?l?? is also presented.

Bilenky, M.; Bilenky, S. M.; Santamaria, A.

1993-03-01

293

Partial proton escape widths of Gamow-Teller resonance  

International Nuclear Information System (INIS)

[en] The method for calculation of giant resonance (GR) partial escape widths has been applied to the calculation of the partial proton escape widths of the Gamow-Teller (GTR) in 9091Zr, 208Pb nuclei. The method has been generalized to the case of nuclei in which the strong neutron pairing takes place. 16 refs

1994-01-01

294

COMPARISON OF THE MANDIBULAR ARCH WIDTHS IN CLEFT PALATE PATIENTS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Mandibular arch widths and ratios are computed for unilateral cleft patients. The mandibular dental arch dimensions in unilateral cleft are different from that of the normals. Studies were made on the arch widths of normals of our population, but the arch dimensions of the cleft patients are not tha...

SUJA ANI G

295

Measuring Slit Width and Separation in a Diffraction Experiment  

Science.gov (United States)

We present a procedure for measuring slit width and separation in single- and double-slit diffraction experiments. Intensity spectra of diffracted laser light are measured with an optical sensor (PIN diode). Slit widths and separations are extracted by fitting to the measured spectra. We present a simple fitting procedure to account for the…

Gan, K. K.; Law, A. T.

2009-01-01

296

Qualitative Logics and Equivalences for Probabilistic Systems  

CERN Document Server

We investigate logics and equivalence relations that capture the qualitative behavior of Markov Decision Processes (MDPs). We present Qualitative Randomized CTL (QRCTL): formulas of this logic can express the fact that certain temporal properties hold over all paths, or with probability 0 or 1, but they do not distinguish among intermediate probability values. We present a symbolic, polynomial time model-checking algorithm for QRCTL on MDPs. The logic QRCTL induces an equivalence relation over states of an MDP that we call qualitative equivalence: informally, two states are qualitatively equivalent if the sets of formulas that hold with probability 0 or 1 at the two states are the same. We show that for finite alternating MDPs, where nondeterministic and probabilistic choices occur in different states, qualitative equivalence coincides with alternating bisimulation, and can thus be computed via efficient partition-refinement algorithms. On the other hand, in non-alternating MDPs the equivalence relations cann...

Chatterjee, Krishnendu; Faella, Marco; Legay, Axel

2009-01-01

297

Equivalent linearization of a squeeze film damper  

Energy Technology Data Exchange (ETDEWEB)

The equivalent linearization of an intershaft squeeze film damper in a two shaft engine system is investigated. The two shaft centers at the damper position are assumed to move in different elliptical offset orbits and at synchronous frequency with the unbalanced rotor (e.g., the high pressure rotor). The nonlinear damper force is resolved into two orthogonal components along the absolute coordinate directions and, in turn, each of these force components is supposed to be equivalent to the sum of an average force, a linear spring force, and a linear damping force in the corresponding direction. By using the method of equivalent linearization by harmonic balance, the six parameters of the equivalent forces, including two average forces, two equivalent spring coefficients, and two equivalent damping coefficients, are expressed analytically by the squeeze film forces and the assumed orbital motion of the two shaft centers at the damper position. 10 references.

Chen, S.; Liu, S.

1986-10-01

298

Homogeneous Dielectric Equivalents of Composite Material Shields  

Directory of Open Access Journals (Sweden)

Full Text Available The paper deals with the methodology of replacing complicated parts of an airplane skin by simple homogeneous equivalents, which can exhibit similar shielding efficiency. On one hand, the airplane built from the virtual homogeneous equivalents can be analyzed with significantly reduced CPU-time demands and memory requirements. On the other hand, the equivalent model can estimate the internal fields satisfactory enough to evaluate the electromagnetic immunity of the airplane.

T. Zvolensky; Z. Raida; P. Tobola

2009-01-01

299

On graph equivalences preserved under extensions  

CERN Document Server

Let R be an equivalence relation on graphs. By the strengthening of R we mean the relation R' such that graphs G and H are in the relation R' if for every graph F, the union of the graphs G and F is in the relation R with the union of the graphs H and F. We study strengthenings of equivalence relations on graphs. The most important case that we consider concerns equivalence relations defined by graph properties. We obtain results on the strengthening of equivalence relations determined by the properties such as being a k-connected graph, k-colorable, hamiltonian and planar.

Lonc, Zbigniew

2010-01-01

300

Derived equivalence of symmetric special biserial algebras  

CERN Document Server

We introduce Brauer complex of symmetric SB-algebra, and reformulate in terms of Brauer complex the so far known invariants of stable and derived equivalence of symmetric SB-algebras. In particular, the genus of Brauer complex turns out to be invariant under derived equivalence. We study transformations of Brauer complexes which preserve class of derived equivalence. Additionally, we establish a new invariant of derived equivalence of symmetric SB-algebras. As a consequence, symmetric SB-algebras with Brauer complex of genus 0 are classified. Keywords: Brauer tree algebras, special biserial algebras, tilting complex.

Antipov, M

2007-01-01

 
 
 
 
301

The equivalent stress concept in multiaxial fatigue  

Directory of Open Access Journals (Sweden)

Full Text Available Some equivalent stress methods, applicable for life prediction in case of multiaxial loading, are presented in this paper, such as empirical equivalent stresses, frequency and “signed von Mises” stress. To apply the latter method, a calculation program that allows the transformation of a fluctuating load cycle into a fully reversed cycle is developed. The authors extend the equivalent stress concept towards critical plane models. This is illustrated by a calculated equivalent shear stress based on the Yokobori criterion. Both the „signed von Mises” and Yokobori approaches have the advantage of allowing multiaxial fatigue calculations for limited durability, as opposed to classical methods which are applicable only for unlimited durability.

DUMITRU Ion; KUN Lorand; DREUCEAN Mircea; MENYHARDT Karoly

2011-01-01

302

Multi-Wavelength Constraints on the Cosmic Star Formation History from Spectroscopy: the Rest-Frame UV, H-alpha, and Infrared Luminosity Functions at Redshifts 1.9  

CERN Multimedia

We use a sample of rest-frame UV selected and spectroscopically observed galaxies at redshifts 1.9H-alpha and Spitzer MIPS 24 micron data, to derive the most robust measurements of the rest-frame UV, H-alpha, and infrared (IR) luminosity functions (LFs) at these redshifts. Our sample is by far the largest of its kind, with over 2000 spectroscopic redshifts in the range 1.9

Reddy, Naveen A; Pettini, Max; Adelberger, Kurt L; Shapley, Alice E; Erb, Dawn K; Dickinson, Mark

2007-01-01

303

Influence of electrical sheet width on dynamic magnetic properties  

International Nuclear Information System (INIS)

Effects of the width of electrical steel sheets on dynamic magnetic properties are investigated by solving diffusion equation on the cross-section of the sheet. Linear and non-linear cases are studied, and are compared with measurement on Epstein frame. For the first one an analytical solution is found, while for the second, a 2D finite element simulation is achieved. The influence of width is highlighted for a width thickness ratio lower than 10. It is shown that the behaviour modification in such cases is conditioned by the excitation signal waveform, amplitude and also frequency

2000-06-02

304

Low-temperature measurement of the giant dipole resonance width  

Energy Technology Data Exchange (ETDEWEB)

The width of the giant dipole resonance (GDR) built on excited states was determined from a measurement of {gamma}-decays in coincidence with {sup 17}O particles scattered inelastically from {sup 120}Sn. The bombarding energy was 80 MeV/u. A width of 4{+-}1 MeV, consistent with the width of the GDR built on the ground state, was found at a temperature T=1 MeV. This result is in disagreement with adiabatic thermal shape fluctuation calculations, indicating an overestimation of the influence of thermal shape fluctuations at low temperature.

Heckman, P.; Bazin, D.; Beene, J.R.; Blumenfeld, Y.; Chromik, M.J.; Halbert, M.L.; Liang, J.F.; Mohrmann, E.; Nakamura, T.; Navin, A.; Sherrill, B.M.; Snover, K.A.; Thoennessen, M.; Tryggestad, E.; Varner, R.L

2003-02-27

305

Influence of electrical sheet width on dynamic magnetic properties  

CERN Multimedia

Effects of the width of electrical steel sheets on dynamic magnetic properties are investigated by solving diffusion equation on the cross-section of the sheet. Linear and non-linear cases are studied, and are compared with measurement on Epstein frame. For the first one an analytical solution is found, while for the second, a 2D finite element simulation is achieved. The influence of width is highlighted for a width thickness ratio lower than 10. It is shown that the behaviour modification in such cases is conditioned by the excitation signal waveform, amplitude and also frequency.

Chevalier, T; Cornut, B

2000-01-01

306

Homogeneous Dielectric Equivalents of Composite Material Shields  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The paper deals with the methodology of replacing complicated parts of an airplane skin by simple homogeneous equivalents, which can exhibit similar shielding efficiency. On one hand, the airplane built from the virtual homogeneous equivalents can be analyzed with significantly reduced CPU-time dema...

T. Zvolensky; Z. Raida; P. Tobola

307

Undecidability of performance equivalence of Petri nets  

CERN Document Server

We investigate bisimulation equivalence on Petri nets under durational semantics. Our motivation was to verify the conjecture that in durational setting, the bisimulation equivalence checking problem becomes more tractable (which is the case, e.g., over communication-free nets). We disprove this conjecture in three of four proposed variants of durational semantics. The fourth case remains an interesting open problem.

Lasota, Slawomir

2009-01-01

308

The therapeutic equivalence of complex drugs  

Digital Repository Infrastructure Vision for European Research (DRIVER)

When the patent of a small molecule drug expires generics may be introduced. They are considered therapeutically equivalent once pharmaceutical equivalence (i.e. identical active substances) and bioequivalence (i.e. comparable pharmacokinetics) have been established in a cross-over volunteer study. ...

Schellekens, H.; Klinger, E.; Mühlebach, S.; Brin, J-F.; Storm, G.; Crommelin, D.J.A.

309

Galeazzi-equivalent lesions in adolescence.  

UK PubMed Central (United Kingdom)

Two cases of a Galeazzi-equivalent lesion in adolescence are described. Accurate diagnosis of the epiphyseal injury of the distal ulna, rigid fixation of the distal radius, and stabilization of the distal radioulnar joint are keys in obtaining a good result in the treatment of Galeazzi-equivalent lesion in adolescence.

Kamano M; Honda Y

2002-07-01

310

Equivalences induced by infinitely generated tilting modules  

CERN Multimedia

We generalize Brenner and Butler's Theorem as well as Happel's Theorem on the equivalences induced by a finitely generated tilting module over artin algebras, to the case of an infinitely generated tilting module over an arbitrary associative ring establishing the equivalences induced between subcategories of module categories and also at the level of derived categories.

Bazzoni, Silvana

2009-01-01

311

The relation between incurvated nail plate width and the transverse width of distal phalanx. A CT scan study  

Energy Technology Data Exchange (ETDEWEB)

To clarify the cause of incurvated nail, the relation between the nail plate and the distal phalanx of the patient of incurvated/ingrown nail and normal subjects was compared, by measuring CT scan images. The investigation was made on 12 incurvated nails, 8 ingrown nails and 8 normal nails of the first toes which were clinically diagnosed as such. Each toe was scanned at 1 mm intervals with the same CT scanner under the same conditions. The pictures taken on the film were scanned and input into a computer. The transverse width of the distal phalanx and the width of the nail plate were measured on each slice. The minimum transverse width of the distal phalanx in both stages of slightly and intensively incurvated nail was smaller as compared to that in the stages of normal nail and ingrown nail. The ratios of the width of the nail plate to the minimum transverse width of the distal phalanx in the stages of normal nail, ingrown nail and intensively incurvated nail were nearly equal, while the ratio in the stage of slightly incurvated nail was outstandingly large. Based on the results of this investigation, it can be considered that the transverse width of the distal phalanx is reduced first, and consequently, the incurvation of the nail plate occurs, then the width of the nail plate is reduced as the incurvation becomes more intense. (author).

Yamaguchi, Akinobu [Showa Univ., Tokyo (Japan). School of Medicine

1995-06-01

312

The relation between incurvated nail plate width and the transverse width of distal phalanx. A CT scan study  

International Nuclear Information System (INIS)

To clarify the cause of incurvated nail, the relation between the nail plate and the distal phalanx of the patient of incurvated/ingrown nail and normal subjects was compared, by measuring CT scan images. The investigation was made on 12 incurvated nails, 8 ingrown nails and 8 normal nails of the first toes which were clinically diagnosed as such. Each toe was scanned at 1 mm intervals with the same CT scanner under the same conditions. The pictures taken on the film were scanned and input into a computer. The transverse width of the distal phalanx and the width of the nail plate were measured on each slice. The minimum transverse width of the distal phalanx in both stages of slightly and intensively incurvated nail was smaller as compared to that in the stages of normal nail and ingrown nail. The ratios of the width of the nail plate to the minimum transverse width of the distal phalanx in the stages of normal nail, ingrown nail and intensively incurvated nail were nearly equal, while the ratio in the stage of slightly incurvated nail was outstandingly large. Based on the results of this investigation, it can be considered that the transverse width of the distal phalanx is reduced first, and consequently, the incurvation of the nail plate occurs, then the width of the nail plate is reduced as the incurvation becomes more intense. (author)

1995-01-01

313

Infinite time decidable equivalence relation theory  

CERN Multimedia

We introduce an analog of the theory of Borel equivalence relations in which we study equivalence relations that are decidable by an infinite time Turing machine. The Borel reductions are replaced by the more general class of infinite time computable functions. Many basic aspects of the classical theory remain intact, with the added bonus that it becomes sensible to study some special equivalence relations whose complexity is beyond Borel or even analytic. We also introduce an infinite time generalization of the countable Borel equivalence relations, a key subclass of the Borel equivalence relations, and again show that several key properties carry over to the larger class. Lastly, we collect together several results from the literature regarding Borel reducibility which apply also to absolutely Delta_1^2 reductions, and hence to the infinite time computable reductions.

Coskey, Samuel

2009-01-01

314

Equivalence in Ventilation and Indoor Air Quality  

Energy Technology Data Exchange (ETDEWEB)

We ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American Society of Heating, Refrigerating, and Air-Conditioning Enginners [ASHRAE] Standard 62) specify minimum ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation management is often a desirable element of reducing energy consumption or improving IAQ or comfort. Variable ventilation is one innovative strategy. To use variable ventilation in a way that meets standards, it is necessary to have a method for determining equivalence in terms of either ventilation or indoor air quality. This study develops methods to calculate either equivalent ventilation or equivalent IAQ. We demonstrate that equivalent ventilation can be used as the basis for dynamic ventilation control, reducing peak load and infiltration of outdoor contaminants. We also show that equivalent IAQ could allow some contaminants to exceed current standards if other contaminants are more stringently controlled.

Sherman, Max; Walker, Iain; Logue, Jennifer

2011-08-01

315

Spin dependence of spread widths of collective quadrupole excitations  

International Nuclear Information System (INIS)

[en] Damping of collective excitations of fast-rotating nuclei has been investigated within the framework of a Fermi liquid drop model with provision for dissipation. Spread widths of collective excitation have been calculated

1986-04-15

316

Widths of some classes of convex functions and bodies  

Energy Technology Data Exchange (ETDEWEB)

We consider classes of uniformly bounded convex functions defined on convex compact bodies in R{sup d} and satisfying a Lipschitz condition and establish the exact orders of their Kolmogorov, entropy, and pseudo-dimension widths in the L{sub 1}-metric. We also introduce the notions of pseudo-dimension and pseudo-dimension widths for classes of sets and determine the exact orders of the entropy and pseudo-dimension widths of some classes of convex bodies in R{sup d}relative to the pseudo-metric defined as the d-dimensional Lebesgue volume of the symmetric difference of two sets. We also find the exact orders of the entropy and pseudo-dimension widths of the corresponding classes of characteristic functions in L{sub p}-spaces, 1{<=}p{<=}{infinity}.

Konovalov, V N [Institute of Mathematics of Ukrainian National Academy of Sciences, Kiev (Ukraine); Maiorov, Vitalii E [Technion - Israel Institute of Technology, Haifa (Israel)

2010-02-28

317

Possible Gigantic Variations on the Width of Viscoelastic Fingers  

CERN Document Server

We analyze the effect of frequency on the width of a single finger displacing a viscoelastic fluid. We derive a generalized Darcy's law in the frequency domain for a linear viscoelastic fluid flowing in a Hele Shaw cell. This leads to an analytic expression for the dynamic permeability that has maxima which are several orders of magnitude larger than the static permeability. We then follow an argument of de Gennes to obtain the smallest possible finger width when viscoelasticity is important. Using this, and a conservation law, we obtain a lowest bound for the width of a single finger displacing a viscoelastic fluid. Our results indicate that when a small amplitude signal of the frequency that maximizes the permeability is overimposed to a constant pressure drop, gigantic variations are obtained for the finger width.

Poire, E C; Poire, Eugenia Corvera

2002-01-01

318

Simple parametrization of fragment reduced widths in heavy ion collisions.  

UK PubMed Central (United Kingdom)

A systematic analysis of the observed reduced widths obtained in relativistic heavy ion fragmentation reactions is used to develop a phenomenological parametrization of these data. The parametrization is simple, accurate, and completely general in applicability.

Tripathi RK; Townsend LW

1994-04-01

319

Estimates for the widths of weighted Sobolev classes  

International Nuclear Information System (INIS)

[en] Estimates for the Kolmogorov widths in the Lq,v-metric of weighted Sobolev classes as well as for the approximation numbers of the corresponding embedding operators are found. Bibliography: 33 titles.

2010-09-02

320

Estimating the Spectral Width of a Narrowband Optical Signal  

DEFF Research Database (Denmark)

Methods for estimating the spectral width of a narrowband optical signal are investigated. Spectral analysis and Fourier spectroscopy are compared. Optimum and close-to-optimum estimators are developed under the constraint of having only one photodetector.

Lading, Lars; Skov Jensen, A.

1980-01-01

 
 
 
 
321

The width of the giant dipole resonance at finite temperature  

International Nuclear Information System (INIS)

A method is proposed to evaluate the effect of the change of the Fermi sea on the width of the giant dipole resonance at finite temperature. In a schematic model it is found that, indeed, in 208Pb the width increases very sharply up to about T=4 MeV but shows a much weaker variation for higher temperature. (author) 26 refs., 7 figs., 2 tabs.

1992-01-01

322

Constant Width Planar Computation Characterizes ACC0  

DEFF Research Database (Denmark)

We obtain a characterization of ACC 0 in terms of a natural class of constant width circuits, namely in terms of constant width polynomial size planar circuits. This is shown via a characterization of the class of acyclic digraphs which can be embedded on a cylinder surface in such a way that all arcs flow along the same direction of the axis of the cylinder.

Hansen, K.A.

2004-01-01

323

Relation between subpulse widths and the polarization properties of pulsars  

Energy Technology Data Exchange (ETDEWEB)

A discussion of the techniques used for estimating the subpulse widths of pulsars concludes that Gaussian fitting has advantages over autocorrelation techniques for single pulse data recorded with millisecond resolution at radio frequencies around 400 MHz. Measurements are presented for 53 pulsars, made from radio observations obtained at Jodrell Bank. A relation is found between the subpulse widths and the polarization properties of the pulsars, which we interpret in terms of current polar-cap models of the radio emission.

Ashworth, M.

1988-01-01

324

Bone Mineral Density Value Dependence on Bone Width  

Directory of Open Access Journals (Sweden)

Full Text Available Dual x-ray absorptiometry (DXA) is the most widely used measurement for the assessment of bone mass in osteoporosis. In clinical measurement, bone width can affect bone mineral parameters. The purpose of this study was to examine the dependence of bone mineral pa-rameters on bone width. In this study, DXA measurements were conducted on rabbit bone in vivo using clinical instruments. We have selected rabbit’s bones that have low BMD and more collagen tissue to predict structure not only measures BMD, but is also sensitive to the structure of the bone. To investigate the effect of bone width on the measured parameters, three regions of femur and tibia bones (N=132) were processed: upper (1/3 of length), middle (1/2 of length) and lower (2/3 of length) for BMC, areal BMD and volumetric BMD. The ANOVA analysis of bone mineral extracted by DXA showed significant differences (P<0.05) between BMC, BMDa and BMDv of six groups of upper, middle and lower parts of the femur and the tibia. It shows that BMC and BMD correlate well with the bone width, but BMDv inversely correlates with bone width. Linear and nonlinear regression analyses were used to examine the relationship between DXA characteristics with bone width and the regression function for each parameter is given. We concluded that BMC, areal BMD, and volumetric BMD in rabbit's bone with collagen fibers more than bone mineral are dependent on bone width. This result may be at least in part due to large precision error measurement of the bone width, in vivo.

M. Mokhtari-Dizaji; M.R. Dadras; B. Larijani

2006-01-01

325

Calculation of the Higgs boson decay widths into boson pairs  

International Nuclear Information System (INIS)

The decay widths of the Higgs boson into ??,Z?,ZZ and W+W- are calculated on the one-loop level of the electroweak theory. Exact analytic formulae in terms of complex-valued dilogarithms are obtained. The dependence of the decay widths on the Higgs boson mass and on the top-quark mass are investigated. 12 refs.; 10 figs.; 1 tab

1991-01-01

326

A direct measurement of W boson decay width  

CERN Multimedia

Based on 85 pb$^{-1}$ data of \\ppbar collisions at $\\sqrt{s}=1.8$ \\tev\\ collected using the D{\\O}detector at Fermilab during the 1994-1995 run of the Tevatron, we present a direct measurement of the total decay width of the \\wb\\ boson, $\\Gamma_W$. The width is determined from the transverse mass spectrum in the $W \\to e+\

Abazov, V M; Abdesselam, A; Abolins, M; Abramov, V; Acharya, B S; Adams, D L; Adams, M; Ahmed, S N; Alexeev, G D; Alton, A; Alves, G A; Anderson, E W; Arnoud, Y; Avila, C; Baarmand, M M; Babintsev, V V; Babukhadia, L; Bacon, Trevor C; Baden, A; Baldin, B Yu; Balm, P W; Banerjee, S; Barberis, E; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Bean, A; Beaudette, F; Begel, M; Belyaev, A; Beri, S B; Bernardi, G; Bertram, I; Besson, A; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Bhattacharjee, M; Blazey, G; Blekman, F; Blessing, S; Böhnlein, A; Bozhko, N; Bolton, T A; Borcherding, F; Bos, K; Bose, T; Brandt, A; Breedon, R; Briskin, G; Brock, R; Brooijmans, G; Bross, A; Buchholz, D; Bühler, M; Büscher, V; Burtovoi, V S; Butler, J M; Canelli, F; Carvalho, W; Casey, D; Casilum, Z; Castilla-Valdez, H; Chakraborty, D; Chan, K M; Chekulaev, S V; Cho, D K; Choi, S; Chopra, S; Christenson, J H; Chung, M; Claes, D; Clark, A R; Coney, L; Connolly, B; Cooper, W E; Coppage, D; Crepe-Renaudin, S; Cummings, M A C; Cutts, D; Davis, G A; De, K; De Jong, S J; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doulas, S; Ducros, Y; Dudko, L V; Duensing, S; Duflot, L; Dugad, S R; Duperrin, A; Dyshkant, A; Edmunds, D; Ellison, J; Eltzroth, J T; Elvira, V D; Engelmann, R; Eno, S; Eppley, G; Ermolov, P; Eroshin, O V; Estrada, J; Evans, H; Evdokimov, V N; Fahland, T; Fein, D; Ferbel, T; Filthaut, Frank; Fisk, H E; Fisyak, Yu; Flattum, E; Fleuret, F; Fortner, M; Fox, H; Frame, K C; Fu, S; Fuess, S; Gallas, E; Galjaev, A N; Gao, M; Gavrilov, V; Genik, R J; Genser, K; Gerber, C E; Gershtein, Yu; Gilmartin, R; Ginther, G; Gómez, B; Goncharov, P I; Gordon, H; Goss, L T; Gounder, K; Goussiou, A; Graf, N; Grannis, P D; Green, J A; Greenlee, H; Greenwood, Z D; Grinstein, S; Groer, L; Grünendahl, S; Sen-Gupta, A; Gurzhev, S N; Gutíerrez, G; Gutíerrez, P; Hadley, N J; Haggerty, H; Hagopian, S; Hagopian, V; Hall, R E; Hansen, S; Hauptman, J M; Hays, C; Hebert, C; Hedin, D; Heinmiller, J M; Heinson, A P; Heintz, U; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Huang, Y; Iashvili, I; Illingworth, R; Ito, A S; Jaffré, M; Jain, S; Jesik, R; Johns, K; Johnson, M; Jonckheere, A; Jöstlein, H; Juste, A; Kahl, W; Kahn, S; Kajfasz, E; Kalinin, A M; Karmanov, D; Karmgard, D; Kehoe, R; Khanov, A; Kharchilava, A I; Kim, S K; Klima, B; Knuteson, B; Ko, W; Kohli, J M; Kostritskii, A V; Kotcher, J; Kothari, B; Kotwal, A V; Kozelov, A V; Kozlovskii, E A; Krane, J; Krishnaswamy, M R; Krivkova, P; Krzywdzinski, S; Kubantsev, M A; Kuleshov, S; Kulik, Y; Kunori, S; Kupco, A; Kuznetsov, V E; Landsberg, G L; Lee, W M; Leflat, A; Leggett, C; Lehner, F; Leonidopoulos, C; Li, J; Li, Q Z; Lima, J G R; Lincoln, D; Linn, S L; Linnemann, J; Lipton, R; Lucotte, A; Lueking, L; Lundstedt, C; Luo, C; Maciel, A K A; Madaras, R J; Malyshev, V L; Manankov, V; Mao, H S; Marshall, T; Martin, M I; Mayorov, A A; McCarthy, R; McMahon, T; Melanson, H L; Merkin, M; Merritt, K W; Miao, C; Miettinen, H; Mihalcea, D; Mishra, C S; Mokhov, N V; Mondal, N K; Montgomery, H E; Moore, R W; Mostafa, M; Da Motta, H; Mutaf, Y; Nagy, E; Nang, F; Narain, M; Narasimham, V S; Naumann, N A; Neal, H A; Negret, J P; Nomerotski, A; Nunnemann, T; O'Neil, D; Oguri, V; Olivier, B; Oshima, N; Padley, P; Pan, L J; Papageorgiou, K; Parashar, N; Partridge, R; Parua, N; Paterno, M; Patwa, A; Pawlik, B; Peters, O; Petroff, P; Piegaia, R; Pope, B G; Popkov, E; Prosper, H B; Protopopescu, S D; Przybycien, M B; Qian, J; Raja, R; Rajagopalan, S; Ramberg, E; Rapidis, P A; Reay, N W; Reucroft, S; Ridel, M; Rijssenbeek, M; Rizatdinova, F K; Rockwell, T; Roco, M T; Royon, C; Rubinov, P; Ruchti, R; Rutherfoord, J; Sabirov, B M; Sajot, G; Santoro, A F S; Sawyer, L; Schamberger, R D; Schellman, H; Schwartzman, A; Sen, N; Shabalina, E; Shivpuri, R K; Shpakov, D; Shupe, M; Sidwell, R A; Simák, V; Singh, H; Sirotenko, V I; Slattery, P F; Smith, E; Smith, R P; Snihur, R; Snow, G R; Snow, J; Snyder, S; Solomon, J; Song, Y; Sorin, V; Sosebee, M; Sotnikova, N; Soustruznik, K; Souza, M; Stanton, N R; Steinbruck, G; Stephens, R W; Stoker, D; Stolin, V; Stone, A; Stoyanova, D A; Strang, M A; Strauss, M; Strovink, M; Stutte, L; Sznajder, A; Talby, M; Taylor, W; Tentindo-Repond, S; Tripathi, S M; Trippe, T G; Turcot, A S; Tuts, P M; Vaniev, V; Van Kooten, R; Varelas, N; Vertogradov, L S; Villeneuve-Séguier, F; Volkov, A A; Vorobev, A P; Wahl, H D; Wang, H; Wang, Z M; Warchol, J; Watts, G; Wayne, M; Weerts, H; White, A; White, J T; Whiteson, D; Wijngaarden, D A; Willis, S; Wimpenny, S J; Womersley, J; Wood, D R; Xu, Q; Yamada, R; Yamin, P; Yasuda, T; Yatsunenko, Y A; Yip, K; Youssef, S; Yu, J; Zanabria, M; Zhang, X; Zheng, H; Zhou, B; Zhou, Z; Zielinski, M; Zieminska, D; Zieminski, A; Zutshi, V; Zverev, E G; Zylberstejn, A

2002-01-01

327

Correlations for reduced-width amplitudes in 49V  

International Nuclear Information System (INIS)

[en] Measurement of the relative sign of inelastic proton-channel amplitudes permits the determination of amplitude correlations. Data were obtained for 45 5/2+ resonances in 49V. Although the reduced widths in each channel followed a Porter-Thomas distribution, large amplitude correlations were observed. The results are compared with the reduced-width--amplitude distribution of Krieger and Porter. This is the first direct test of the Krieger-Porter distribution

1980-10-13

328

Correlations for reduced-width amplitudes in /sup 49/V  

Energy Technology Data Exchange (ETDEWEB)

Measurement of the relative sign of inelastic proton-channel amplitudes permits the determination of amplitude correlations. Data were obtained for 45 5/2/sup +/ resonances in /sup 49/V. Although the reduced widths in each channel followed a Porter-Thomas distribution, large amplitude correlations were observed. The results are compared with the reduced-width--amplitude distribution of Krieger and Porter. This is the first direct test of the Krieger-Porter distribution.

Chou, B.H.; Mitchell, G.E.; Bilpuch, E.G.; Westerfeldt, C.R.

1980-10-13

329

Ridge Width Gain With Screw Spreaders: A Cadaver Study.  

UK PubMed Central (United Kingdom)

BACKGROUND:: The aim of this cadaver study was to evaluate the amount of ridge expansion with screw spreaders. METHODS:: Eleven edentulous maxillae providing 20 eligible sites were used. Ridges with initial width of 3 to 6 mm were expanded using a set of 6 screw spreaders, and implants (ø3.7 × 10 mm) were subsequently placed. Ridge width at 2 mm apical to the crest was measured at the baseline, after expansion, and implant placement. Buccal plate thickness and incidence of buccal dehiscence after implant placement were measured. RESULTS:: The mean initial ridge width was 3.97 ± 0.82 mm. After the expansion, the mean ridge width increased to 4.76 ± 0.77 mm ([INCREMENT] = 0.79 mm). Majority of sites (7/9 sites) with an initial ridge width of <4 mm had a buccal dehiscence after implant placement. A buccal plate thickness of ?1 mm was consistently present in cases with an initial ridge width of ?4.5 mm after implant placement. CONCLUSIONS:: The screw spreaders had a modest effect on ridge expansion. Their use might be limited because additional bone augmentation might be required to prevent or correct the bony dehiscence encountered in ridges <4.5 mm wide. Therefore, using this particular instrument kit for horizontal ridge augmentation is only indicated in specific cases.

Chan HL; Fu JH; Koticha T; Benavides E; Wang HL

2013-09-01

330

Stieltjes-moment-theory technique for calculating resonance width's  

International Nuclear Information System (INIS)

[en] A recently developed method for calculating the widths of atomic and molecular resonances is reviewed. The method is based on the golden-rule definition of the resonance width, GAMMA(E). The method uses only square-integrable, L2, basis functions to describe both the resonant and the non-resonant parts of the scattering wave function. It employs Stieltjes-moment-theory techniques to extract a continuous approximation for the width discrete representation of the background continuum. Its implementation requires only existing atomic and molecular structure codes. Many-electron effects, such as correlation and polarization, are easily incorporated into the calculation of the width via configuration interaction techniques. Once the width, GAMMA(E), has been determined, the energy shift can be computed by a straightforward evaluation of the required principal-value integral. The main disadvantage of the method is that it provides only the total width of a resonance which decays into more than one channel in a multichannel problem. A review of the various aspects of the theory is given first, and then representative results that have been obtained with this method for several atomic and molecular resonances are discussed. 28 references, 3 figures, 4 tables

1978-01-01

331

A Measurement of the Total Width, the Electronic Width and the Mass of the Upsilon(10580) Resonance  

CERN Document Server

We present a preliminary measurement of the resonance parameters of the Upsilon(10580) resonance with the BABAR detector at the SLAC PEP-II asymmetric B factory. We measure the total decay width to be (20.7 +- 1.6 +- 2.5) MeV, the partial electronic width to be (0.321 +- 0.017 +- 0.029) kev and the mass to be (10.5793 +- 0.0004 +- 0.0012) GeV.

Aubert, Bernard; Abe, T; Abrams, G S; Adye, T; Ahmed, S; Alam, M S; Albert, J; Aleksan, Roy; Allison, J; Altenburg, D; Andreotti, M; Angelini, C; Anulli, F; Aston, D; Azzolini, V; Baak, M A; Back, J J; Bailey, S; Baldini-Ferroli, R; Band, H R; Banerjee, Sw; Barate, R; Barlow, N R; Barlow, R J; Bartoldus, R; Batignani, G; Bauer, J M; Beck, T W; Behera, P K; Bellini, F; Benayoun, M; Berger, N; Beringer, J; Bernard, D; Berryhill, J W; Best, D; Bettarini, S; Bettoni, D; Bevan, A J; Bhimji, W; Bianchi, F; Biasini, M; Blanc, F; Blaylock, G; Blinov, V E; Bloom, P; Bondioli, M; Bonneaud, G R; Borean, C; Borgland, A W; Bosisio, L; Boutigny, D; Bowerman, D A; Boyarski, A M; Boyd, J T; Bozzi, C; Brandt, T; Brau, B; Brau, J E; Breon, A B; Briand, H; Brigljevic, V; Brochard, F; Brose, J; Brown, C L; Brown, C M; Brown, D; Brown, D N; Bruinsma, M; Brunet, S; Bucci, F; Buchanan, C; Buchmüller, O L; Bugg, W; Bukin, A D; Burchat, Patricia R; Button-Shafer, J; Buzzo, A; Bóna, M; Cahn, R N; Calabrese, R; Calcaterra, A; Calderini, G; Campagnari, C; Capra, R; Carpinelli, M; Cartaro, C; Cavallo, N; Cavoto, G; Chao, M; Charles, E; Chauveau, J; Chen, E; Chen, J C; Chen, S; Cheng, C H; Chevalier, N; Christ, S; Cibinetto, G; Clark, P J; Cochran, J; Cohen-Tanugi, J; Colberg, T; Colecchia, F; Coleman, J P; Contri, R; Convery, M R; Cote-Ahern, D; Cottingham, W N; Coupal, D P; Cowan, G; Cowan, R; Crawley, H B; Cremaldi, L M; Crosetti, G; Dahmes, B; Dallapiccola, C; Danielson, N; Dasu, S; Datta, M; Dauncey, P D; David, P; Davier, M; Davis, C L; Day, C T; De Groot, N; De Nardo, Gallieno; De Sangro, R; Del Buono, L; Del Gamba, V; Del Re, D; Della Ricca, G; Di Lodovico, F; Dickopp, M; Dittongo, S; Donald, M; Dong, D; Dorfan, J; Dorigo, A; Dubitzky, R S; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W M; Dvoretskii, A; Eckmann, R; Edwards, A J; Egede, U; Eichenbaum, A M; Eigen, G; Eisner, A M; Elmer, P; Emery, S; Ernst, J A; Eschenburg, V; Eschrich, I; Fabozzi, F; Faccini, R; Falciai, D; Farbin, A; Ferrarotto, F; Ferroni, F; Field, R C; Finocchiaro, G; Fisher, A; Flack, R L; Flächer, H U; Flood, K T; Ford, K; Ford, W T; Forti, A C; Forti, F; Fortin, D; Franek, B J; Frey, R; Fry, J R; Gabathuler, Erwin; Gabriel, T A; Gaidot, A; Gaillard, J M; Gaillard, J R; Galeazzi, F; Gallo, F; Gamba, D; Gamet, R; Gan, K K; Ganzhur, S F; Gaspero, M; Gatto, C; Geddes, N I; George, S; Gill, M S; Giorgi, M A; Giraud, P F; Gladney, L; Glanzman, T; Godang, R; Goetzen, K; Golubev, V B; Gopal, G P; Gowdy, S J; Grancagnolo, S; Graugès-Pous, E; Green, M G; Grenier, G J; Grenier, P; Gritsan, A V; Grosdidier, G; Groysman, Y; Guo, Q H; Hadavand, H K; Hadig, T; Haire, M; Halyo, V; Hamel de Monchenault, G; Hamon, O; Harrison, P F; Harrison, T J; Hart, P A; Hartfiel, B L; Harton, J L; Hast, C; Hauke, A; Hawkes, C M; Hearty, C; Held, T; Hertzbach, S S; Heusch, C A; Hicheur, A; Hill, E J; Hitlin, D G; Hodgkinson, M C; Honscheid, K; Hrynóva, T; Hu, T; Hufnagel, D; Höcker, A; Innes, W R; Ivanchenko, V N; Izen, J M; Jackson, F; Jackson, P D; Jacobsen, R G; Jawahery, A; Jayatilleke, S M; Jessop, C P; John, M J J; Johnson, J R; Judd, D; Kadel, R W; Kadyk, J; Kagan, H; Karyotakis, Yu; Kass, R; Kay, M; Kelly, M P; Kelsey, M H; Kerth, L T; Khan, A; Kim, H; Kim, P; Kirkby, D; Kitayama, I; Knowles, D J; Koch, H; Kocian, M L; Kofler, R; Kolomensky, Yu G; Koptchev, V B; Kovalskyi, D; Kowalewski, R V; Kozanecki, Witold; Kral, J F; Kravchenko, E A; Krishnamurthy, M; Kroeger, R; Kukartsev, G; Kurup, A; Kutter, P E; Kuznetsova, N; Kyberd, P; La Vaissière, C de; Lacker, H M; Lae, C K; Lafferty, G D; Lamsa, J; Lanceri, L; Lange, D J; Langenegger, U; Langer, M; Lankford, A J; Laplace, S; Latham, T E; Lavin, D; Lazzaro, A; Le Clerc, C; Le Diberder, F R; Lee, S J; Lees, J P; Legendre, M; Leith, D W G S; Lepeltier, V; Leruste, P; Levesque, J A; Levi, M E; Levy, S L; Lewandowski, B; Li, H; Lillard, V; Lista, L; Liu, R; Lo Vetere, M; LoSecco, J M; Lockman, W S; London, G W; Long, O; Lou, X C; Lu, A; Luitz, S; Luppi, E; Lusiani, A; Lutz, A M; Lynch, G; Lynch, H L; Lyon, A J; Lü, C; Lüth, V; MacFarlane, D B; MacKay, C; Macri, M; Mallik, U; Maly, E; Mancinelli, G; Mandelkern, M A; Manfredi, P F; Mangeol, D J J; Marchiori, G; Margoni, M; Marker, C E; Marsiske, H; Martínez-Vidal, F; Mattison, T S; Mayer, B; Mazur, M A; Mazzoni, M A; McKemey, A K; McKenna, J A; McMahon, T R; Meadows, B T; Messner, R; Meyer, T I; Meyer, W T; Miftakov, V; Mihályi, A; Mir, L M; Mohapatra, A K; Mommsen, R K; Monge, M R; Moore, T B; Morandin, M; Morgan, S E; Morganti, M; Morganti, S; Morii, M; Morton, G W; Muheim, F; Müller, D R; Müller-Pfefferkorn, R; Narsky, I; Nash, J A; Nauenberg, U; Neal, H; Negrini, M; Neri, N; Nicholson, H; Nogowski, R; O'Grady, C P; Ocariz, J; Oddone, P J; Ofte, I; Olaiya, E O; Olivas, A; Olsen, J; Onuchin, A P; Orimoto, T J; Otto, S; Ozcan, V E; Paar, H P

2003-01-01

332

Low dimension equivalence in reactor physics calculations  

International Nuclear Information System (INIS)

[en] A definition of low dimension equivalence in reactor physics calculations is given. Introducing a leakage buckling BL2, the axial equivalence equation for one dimension, as an example, is developed by the conservation of neutron and the weighted residual method in physics and mathematics respectively. YPARAM code has been developed to calculate the one dimension equivalence parameters. The eqivalent 1-D results are compared with the 3-D results for a 3-D test problem. The calculation errors of Keff and power distribution are within the accuracy limits of engineering design

1988-01-01

333

Fluctuation of Dirac operator and equivalence principle  

CERN Multimedia

General Relativity formulated with Noncommutative geometry allows one to obtain, via the fluctuation of Dirac operator, an exact equivalence principle: generation of curvature and torsion from flat space. The fluctuation method presented in this report is applied on two examples.

Marciante, Mathieu

2012-01-01

334

Equivalence Principle, Higgs Boson and Cosmology  

Directory of Open Access Journals (Sweden)

Full Text Available We discuss here possible tests for Palatini f(R)-theories together with their implications for different formulations of the Equivalence Principle. We shall show that Palatini f(R)-theories obey the Weak Equivalence Principle and violate the Strong Equivalence Principle. The violations of the Strong Equivalence Principle vanish in vacuum (and purely electromagnetic) solutions as well as on short time scales with respect to the age of the universe. However, we suggest that a framework based on Palatini f(R)-theories is more general than standard General Relativity (GR) and it sheds light on the interpretation of data and results in a way which is more model independent than standard GR itself.

Lorenzo Fatibene; Mauro Francaviglia

2013-01-01

335

Derived equivalences in n-angulated categories  

CERN Multimedia

In this paper, we consider $n$-perforated Yoneda algebras for $n$-angulated categories, and show that, under some conditions, $n$-angles induce derived equivalences between the quotient algebras of $n$-perforated Yoneda algebras. This result generalizes some results of Hu, K\\"{o}nig and Xi. And it also establishes a connection between higher cluster theory and derived equivalences. Namely, in a cluster tilting subcategory of a triangulated category, any Auslander-Reiten $n$-angle implies a derived equivalence between two quotient algebras. This result can be compared with the fact that an Auslander-Reiten sequence suggests a derived equivalence between two algebras which was proved by Hu and Xi.

Chen, Yiping

2011-01-01

336

Singular equivalences induced by homological epimorphisms  

CERN Document Server

We prove that a certain homological epimorphism between two algebras induces a triangle equivalence between their singularity categories. Applying the result to a construction of matrix algebras, we describe the singularity categories of some non-Gorenstein algebras.

Chen, Xiao-Wu

2011-01-01

337

Derived equivalence and non-vanishing loci  

CERN Multimedia

The paper proposes and motivates a conjecture on the invariance of cohomological support loci under derived equivalence. It contains a proof in the case of surfaces, and explains further developments and consequences.

Popa, Mihnea

2012-01-01

338

Observational equivalences for linear logic CC languages  

CERN Multimedia

Linear logic Concurrent Constraint programming (LCC) is an extension of concurrent constraint programming (CC) where the constraint system is based on Girard's linear logic instead of the classical logic. In this paper we address the problem of program equivalence for this programming framework. For this purpose, we present a structural operational semantics for LCC based on a label transition system and investigate different notions of observational equivalences inspired by the state of art of process algebras. Then, we demonstrate that the asynchronous \\pi-calculus can be viewed as simple syntactical restrictions of LCC. Finally we show LCC observational equivalences can be transposed straightforwardly to classical Concurrent Constraint languages and Constraint Handling Rules, and investigate the resulting equivalences.

Haemmerlé, Rémy

2011-01-01

339

Postgraduate year one pharmacy residency program equivalency.  

UK PubMed Central (United Kingdom)

In 2006, the American College of Clinical Pharmacy (ACCP) charged the Task Force on Residency Equivalency to define the professional experience expected of a clinically mature practitioner that would meet or exceed the knowledge and skills of an accredited postgraduate year one residency-trained pharmacist. In this commentary, the Task Force discusses both the qualitative and quantitative components of documentation by means of a residency equivalency portfolio. The potential roles of academia, pharmacy professional organizations, and employers and the possible barriers to an equivalency process are addressed. This commentary lays the foundation for establishing a residency equivalency process that could promote the growth and development of existing and future residency programs and allow qualified practitioners to demonstrate their capabilities. The ACCP implores invested stakeholders to take an active part in this collaborative effort as the profession transitions toward residency training as a prerequisite for all pharmacists providing direct patient care by 2020.

Jordan CJ; Wall GC; Lobo B; Wilkinson J; Creekmore FM; Sorrells K; Hartis C; Miller S; Uchal L

2009-12-01

340

Equivalence Principle and Bound Kinetic Energy  

CERN Multimedia

We consider the role of the internal kinetic energy of bound systems of matter in tests of the Einstein equivalence principle. Using the gravitational sector of the standard model extension, we show that stringent limits on equivalence principle violations in antimatter can be indirectly obtained from tests using bound systems of normal matter. We estimate the bound kinetic energy of nucleons in a range of light atomic species using Green's function Monte Carlo calculations, and for heavier species using a Woods-Saxon model. We survey the sensitivities of existing and planned experimental tests of the equivalence principle, and report new constraints at the level of between a few parts in $10^{6}$ and parts in $10^{8}$ on violations of the equivalence principle for matter and antimatter.

Hohensee, Michael A; Wiringa, R B

2013-01-01

 
 
 
 
341

Indication of extended chromospheres in line width-luminosity relations  

Energy Technology Data Exchange (ETDEWEB)

Measurements of Mg II k, Ca II K, and H..cap alpha.. line widths in late-type stars are compiled together with stellar basic parameters and the net radiative losses of their chromospheres estimated from the Mg II emission line intensities. We found that in giants and supergiants the Mg II k1 width corrected for activity and abundance difference (W1*) shows a different power dependence on the stellar surface gravity from that in dwarfs. The widths of Mg II k and Ca II K lines are linearly correlated even in these giants and supergiants and suggests that the density-dependent effects of the partial frequency redistribution are not the cause of the change in the power index in W1*(k). These facts indicate that the extended chromosphere is a universal phenomenon in the low-gravity late-type stars. The width of H..cap alpha.. shows a nearly constant velocity field in the chromosphere irrespective of gravity, providing that in hybrid stars a small portion of the systematic outflow velocity is superposed on the intrinsic width.

Watanabe, Tetsuya

1988-01-01

342

Capacitor charging FET switcher with controller to adjust pulse width  

Energy Technology Data Exchange (ETDEWEB)

A switching power supply includes an FET full bridge, a controller to drive the FETs, a programmable controller to dynamically control final output current by adjusting pulse width, and a variety of protective systems, including an overcurrent latch for current control. Power MOSFETS are switched at a variable frequency from 20-50 kHz to charge a capacitor load from 0 to 6 kV. A ferrite transformer steps up the DC input. The transformer primary is a full bridge configuration with the FET switches and the secondary is fed into a high voltage full wave rectifier whose output is connected directly to the energy storage capacitor. The peak current is held constant by varying the pulse width using predetermined timing resistors and counting pulses. The pulse width is increased as the capacitor charges to maintain peak current. A digital ripple counter counts pulses, and after the desired number is reached, an up-counter is clocked. The up-counter output is decoded to choose among different resistors used to discharge a timing capacitor, thereby determining the pulse width. A current latch shuts down the supply on overcurrent due to either excessive pulse width causing transformer saturation or a major bridge fault, i.e., FET or transformer failure, or failure of the drive circuitry.

Mihalka, Alex M. (Livermore, CA)

1986-01-01

343

S-equivalents lagrangians in generalized mechanics  

International Nuclear Information System (INIS)

The problem of s-equivalent lagrangians is considered in the realm of generalized mechanics. Some results corresponding to the ordinary (non-generalized) mechanics are extended to the generalized case. A theorem for the reduction of the higher order lagrangian description to the usual order is found to be useful for the analysis of generalized mechanical systems and leads to a new class of equivalence between lagrangian functions. Some new perspectives are pointed out. (Author)

1985-01-01

344

Arthroscopic transosseous-equivalent rotator cuff repair.  

UK PubMed Central (United Kingdom)

Rotator cuff repair techniques continue to evolve in an effort to improve repair biomechanics, maximize the biologic environment for tendon healing, and ultimately improve patient outcomes. The arthroscopic transosseous-equivalent technique was developed to replicate the favorable tendon-bone contact area for healing seen in open transosseous tunnel repair. In this technical note and accompanying video, we present our all-arthroscopic transosseous-equivalent rotator cuff repair technique with a focus on technical pearls.

Lavery KP; Rasmussen JF; Dhawan A

2013-05-01

345

Explicit Homotopy Equivalences Between Some Operads  

CERN Multimedia

In this work we present an explicit operad morphism that is also a homotopy equivalence between the operad given by the real Fulton MacPherson compactification of configuration spaces and the little $n$-disks operad. In particular, the construction gives an operadic homotopy equivalence between the associahedra and the little intervals explicitly. It can also be extended to the case of Kontsevich compactification and Voronov swiss-cheese operad.

Hoefel, Eduardo

2011-01-01

346

On the generation of equivalent hamiltonians  

International Nuclear Information System (INIS)

A new approach to the equivalence problem (in phase space) is presented. Given a Hamiltonian describing a system of particles with two degrees of freedom (and the corresponding Hamilton-Jacobi equation), it is shown how to find the most general family of Hamiltonian functions that generates new Hamilton-Jacobi equation with the following (and essential) characteristic, here defined as equivalence: every new solution is also a solution of the original Hamilton-Jacobi equation and vice-versa. (Author).

1985-01-01

347

Shift Equivalence and the Conley index  

CERN Document Server

In this paper we introduce filtration pairs for isolated invariant sets of continuous maps. We prove the existence of filtration pairs and show that, up to shift equivalence, the induced map on the corresponding pointed space is an invariant of the isolated invariant set. Moreover, the maps defining the shift equivalence can be chosen canonically. Lastly, we define partially ordered Morse decompositions and prove the existence of Morse set filtrations for such decompositions.

Franks, J; Franks, John; Richeson, David

1999-01-01

348

Criteria equivalent to the Riemann Hypothesis  

CERN Multimedia

We give a brief overview of a few criteria equivalent to the Riemann Hypothesis. Next we concentrate on the Riesz and B{\\'a}ez-Duarte criteria. We proof that they are equivalent and we provide some computer data to support them. It is not compressed to six pages version of the talk delivered by M.W. during the XXVII Workshop on Geometrical Methods in Physics, 28 June -- 6 July, 2008, Bia{\\l}owie{\\.z}a, Poland.

Cislo, J

2008-01-01

349

Quantum equivalence of dual field theories  

Energy Technology Data Exchange (ETDEWEB)

Motivated by the study of ultraviolet properties of different versions of supergravities duality transformations at the quantum level are discussed. Using the background field method it is proven on shell quantum equivalence for several pairs of dual field theories known to be classically equivalent. The examples considered include duality in chiral model, duality of scalars and second rank antisymmetric gauge tensors, vector duality and duality of the Einstein theory with cosmological term and the Eddington-Schroedinger theory.

Fradkin, E.S.; Tseytlin, A.A.

1985-06-01

350

Magnetic island widths due to field perturbations in toroidal stellarators  

International Nuclear Information System (INIS)

An explicit formulation is presented to determine widths of magnetic island separatrices generated by magnetic field perturbations in a general toroidal stellarator geometry. The method, which is based on a representation of three-dimensional flux surfaces by double Fourier series, allows rapid and accurate calculation of the island widths in real vacuum field configurations, without the need to follow field lines through numerical integration of the field line equations. The procedure does not involve any simplifying approximations and can be used for fields with multiple small perturbations. Numerical results of the island width obtained in the flux co-ordinate representation for the Advanced Toroidal Facility agree closely with those determined from Poincare puncture points obtained by following field lines. The effects of resonance coupling are analysed. (author). Letter-to-the-editor. 19 refs, 1 fig., 3 tabs.

1990-01-01

351

Gluonia enhancements of the Higgs boson hadronic widths  

International Nuclear Information System (INIS)

[en] We use scalar gluonia dominance of the anomalous trace of the energy-momentum tensor and some results from QCD low-energy theorems and spectral sum rules in order to analyze the hadronic and ?? widths of a light Higgs boson of the standard model with a mass below the charm threshold. Large enhancements of the ?? and ??' modes occur respectively on the top of the ?(0.9) and G(1.6) poles, while the ?? width can be important around the G mass. Consequently, the Higgs into ?+?- branching ratio, which is about 10-2 on these gluonia poles, is much smaller than naively expected. Values of these various widths versus the Higgs boson mass are given. A search for the Higgs boson from the study of the ?? and ?'? invariant masses could be feasible. (orig.)

1989-09-28

352

Fast Width Detection in Corridor Using Hough Transform  

Directory of Open Access Journals (Sweden)

Full Text Available For many robotics and smart car applications it is vitally important to calculate the width. The present paper proposes a new approach for finding the width of a corridor within a constructed image frame that would keep a robot on a safe track away from walls. The main advantage of this approach is less computation time and hence faster response for path recognition. In this new approach, the Hugh Transform technique is also used as the basis of the provided algorithm. Within the determination of corridor width, in order to avoid the accident in the future researches, some approaches such as identify open space, modeling and reconstruction of three-dimensional space, can also be used.

Mehrdad Javadi; Mehdi Ebrahimi

2012-01-01

353

Experimental Stark widths of xenon II spectral lines  

Energy Technology Data Exchange (ETDEWEB)

Stark widths of many prominent 6s-6p and 5d-6p transitions have been measured and compared with theoretical results. A high current pinched discharge was used as a spectroscopic source. Electron density and temperature were estimated in 2.65x10{sup 22} m{sup -3} and 1.45x10{sup 4} K respectively. Experimental Stark widths agree well with previous theoretical results. Our data are compared with those of other authors concerning to the homologous ions Ne II, Ar II, Kr II and Xe II. (orig.).

Bertuccelli, D.; Bertuccelli, G.; Rocco, H.O. di (Inst. de Fisica Arroyo Seco, Dept. de Fisica, Univ. Nacional del Centro de la Provincia de Buenos Aires, Tandil (Argentina))

1991-05-01

354

Widths of the isobaric analog state of /sup 208/Pb  

Energy Technology Data Exchange (ETDEWEB)

Both escape and spreading widths are evaluated microscopically in a consistent framework for the isobaric analog of the /sup 206/Pb ground state. A TDA Green function is obtained within the space of discretized J=0/sup +/ proton-particle neutron-hole configurations using the Skyrme interaction. Couplings of these configurations with continuum and more complicated configurations are included into TDA matrix elements with a form of energy dependent terms. The energy and the widths of the isobaric analog resonance are obtained as a result of the matrix diagonalization. Comparison is made of the results with the former theoretical calculations as well as experimental data.

Adachi, Shizuko; Yoshida, Shiro

1987-01-19

355

Shift adn width of HeII lines  

International Nuclear Information System (INIS)

Based on a quantum statistical many-particle theory, the shift and the width of some He II lines have been evaluated. Ion dynamics have been treated within the model microfield method. Furthermore, fine structure splitting has been taken into account in order to check whether this effect is the cause for the existing large discrepancies between theoretical and experimental line widths. Besides the electronic contributions to the line shift, the shift due to the inhomogeneities of the ionic microfield as well as that due to the quadratic Stark effect has been included. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

1998-10-01

356

Stress estimates from the length/width ratios of fractures  

Energy Technology Data Exchange (ETDEWEB)

The hypothesis is advanced that, provided Young's modulus and Poisson's ratio of the rock are known, the length/width ratios of tension fractures can be used to estimate the tensile stress (assumed constant along the length of each fracture) at the time of fracture formation. The hypothesis is tested on a fissure swarm in 10,000-yr- old basaltic lava in Iceland. The length/width ratios of the fissure give the average tensile stress as of the order of a few MPa. 12 references.

Gudmundsson, A.

1983-01-01

357

Coherent bremsstrahlung and GDR width from 252Cf cold fission  

CERN Multimedia

The energy spectrum of the high energy gamma-rays in coincidence with the prompt gamma rays has been measured for the spontaneous fission of 252Cf. The nucleus-nucleus coherent bremsstrahlung of the accelerating fission fragments is observed and the result has been substantiated with a theoretical calculation based on the coulomb acceleration model. The width of the giant dipole resonance (GDR) decay from the excited fission fragments has been extracted for the first time and compared with the thermal shape fluctuation model (TSFM) in the liquid drop formalism. The extracted GDR width is significantly smaller than the predictions of TSFM.

Pandit, Deepak; Bhattacharya, Srijit; Pal, Surajit; De, A; Banerjee, S R

2009-01-01

358

Coherent bremsstrahlung and GDR width from 252Cf cold fission  

International Nuclear Information System (INIS)

[en] The energy spectrum of the high energy ?-rays in coincidence with the prompt ?-rays has been measured for the spontaneous fission of 252Cf. The nucleus-nucleus coherent bremsstrahlung of the accelerating fission fragments is observed and the result has been substantiated with a theoretical calculation based on the Coulomb acceleration model. The width of the giant dipole resonance (GDR) decay from the excited fission fragments has been extracted for the first time and compared with the thermal shape fluctuation model (TSFM) in the liquid drop formalism. The extracted GDR width is significantly smaller than the predictions of TSFM.

2010-07-05

359

Measuring slit width and separation in a diffraction experiment  

Energy Technology Data Exchange (ETDEWEB)

We present a procedure for measuring slit width and separation in single- and double-slit diffraction experiments. Intensity spectra of diffracted laser light are measured with an optical sensor (PIN diode). Slit widths and separations are extracted by fitting to the measured spectra. We present a simple fitting procedure to account for the integration (averaging) of light across the finite sensor aperture. This experiment provides students with a quantitative, in-depth verification of diffraction theory, as well as hands-on experience in sophisticated fitting methods.

Gan, K K; Law, A T [Department of Physics, Ohio State University, Columbus, OH 43210 (United States)], E-mail: gan@mps.ohio-state.edu

2009-11-15

360

Quantum numbers and decay widths of the psi (3095)  

International Nuclear Information System (INIS)

[en] We present cross sections for e+e-? hadrons, e+e-, and ?+?- near 3095 MeV. The psi (3095) resonance is established as having an assignment J/supP//supC/=1--. The mass is 3095 plus-or-minus4 MeV. The partial width to electrons is GAMMA/sube/=4.8plus-or-minus0.6 keV and the total width GAMMA=69plus-or-minus15 keV. Total rates and interference measurements for the lepton channels are in accord with ?-e universality

1975-05-26

 
 
 
 
361

Statistical analysis of s-wave neutron reduced widths  

International Nuclear Information System (INIS)

[en] The fluctuations of the s-wave neutron reduced widths for many nuclei have been analyzed with emphasis on recent measurements by a statistical procedure which is based on the method of maximum likelihood. It is shown that the s-wave neutron reduced widths of nuclei follow single channel Porter Thomas distribution (x2-distribution with degree of freedom ? = 1) for most of the cases. However there are apparent deviations from ? = 1 and possible explanation and significance of this deviation is given. These considerations are likely to modify the evaluation of neutron cross section. (author)

1992-01-01

362

Statistical analysis of P-wave neutron reduced widths  

International Nuclear Information System (INIS)

[en] The fluctuations of the p-wave neutron reduced widths for fifty one nuclei have been analyzed with emphasis on recent measurements by a statistical procedure which is based on the method of maximum likelihood. It is shown that the p-wave neutron reduced widths of even-even nuclei fallow single channel Porter Thomas distribution (?2-distribution with degree of freedom ?=1) for most of the cases where there are no intermediate structure. It is emphasized that the distribution in nuclei other than even-even may differ from a ?2-distribution with one degree of freedom. Possible explanation and significance of this deviation from ?=1 is given. (author)

2000-01-01

363

Cartan equivalence problem for third order differential operators  

CERN Document Server

This article is dedicated to solve the equivalence problem for two third order differential operators on the line under general fiber--preserving transformation using the Cartan method of equivalence. We will do three versions of the equivalence problems: first via the direct equivalence problem, second equivalence problem is to determine conditions on two differential operators such that there exists a fiber-preserving transformations mapping one to the other according to gauge equivalence and last via fully projective equivalence method.

Nadjafikhah, Mehdi

2011-01-01

364

Ideals and Formal Morita Equivalence of Algebras  

CERN Multimedia

Motivated by deformation quantization, we introduced in an earlier work the notion of formal Morita equivalence in the category of $^*$-algebras over a ring $\\ring C$ which is the quadratic extension by $\\im$ of an ordered ring $\\ring R$. The goal of the present paper is twofold. First, we clarify the relationship between formal Morita equivalence, Ara's notion of Morita $^*$-equivalence of rings with involution, and strong Morita equivalence of $C^*$-algebras. Second, in the general setting of $^*$-algebras over $\\ring C$, we define `closed' $^*$-ideals as the ones occuring as kernels of $^*$-representations of these algebras on pre-Hilbert spaces. These ideals form a lattice which we show is invariant under formal Morita equivalence. This result, when applied to Pedersen ideals of $C^*$-algebras, recovers the so-called Rieffel correspondence theorem. The triviality of the minimal element in the lattice of closed ideals, called the `minimal ideal', is also a formal Morita invariant and this fact can be used ...

Bursztyn, H; Bursztyn, Henrique; Waldmann, Stefan

2000-01-01

365

A Directional Dose Equivalent Monitor for Neutrons  

International Nuclear Information System (INIS)

A directional dose equivalent monitor is introduced which consists of a 30 cm diameter spherical phantom hosting a superheated drop detector embedded at a depth of 10 mm. The device relies on the similarity between the fluence response of neutron superheated drop detectors based on halocarbon-12 and the quality-factor-weighted kerma factor. This implies that these detectors can be used for in-phantom dosimetry and provide a direct reading of dose equivalent at depth. The directional dose equivalent monitor was characterised experimentally with fast neutron calibrations and numerically with Monte Carlo simulations. The fluence response was determined at angles of 0, 45, 90, 135 and 180 degrees for thermal to 20 MeV neutrons. The response of the device is closely proportional to the fluence-to-directional dose equivalent conversion coefficient, H'F(10;a,E). Therefore, our monitor is suitable for a direct measurement of neutron directional dose equivalent, H'(10), regardless of angle and energy distribution of the neutron fluence. (author)

2001-01-01

366

On the equivalence of bound state solutions  

CERN Multimedia

In this paper we show the equivalence of various (non-threshold) bound state solutions of branes, or equivalently branes in background potentials, in ten- and eleven-dimensional supergravity. We compare solutions obtained in two very different ways. One method uses a zero mode analysis to make an Ansatz which makes it possible to solve the full non-linear supergravity equations. The other method utilises T-duality techniques to turn on the fields on the brane. To be specific, in eleven dimensions we show the equivalence for the (M2,M5) bound state, or equivalently an M5-brane in a C_3 field, where we also consider the (MW,M2,M2',M5) solution, which can be obtained from the (M2,M5) bound state by a boost. In ten dimensions we show the equivalence for the ((F,D1),D3) bound state as well as the bound states of (p,q) 5-branes with lower dimensional branes in type IIB, corresponding to D3-branes in B_2 and C_2 fields and (p,q) 5-branes in B_2, C_2 and C_4 fields. We also comment on the recently proposed V-duality ...

Gran, U G; Gran, Ulf; Nielsen, Mikkel

2001-01-01

367

Width of giant dipole resonance in hot nuclei  

Energy Technology Data Exchange (ETDEWEB)

An approach describing the width of the giant dipole resonance in hot nuclei is proposed. The numerical calculations in the schematic model with equally degenerate equidistant shells for a hot nucleus of mass A=110 carrying no angular momentum are performed which provide a good agreement with the behavior of the recent experimental data. (authors). 30 refs., 5 figs.

Dinh Dang, N. [Viet Nam National Atomic Energy Commission, Hanoi (Viet Nam); Baldo, M. [Istituto Nazionale di Fisica Nucleare, Catania (Italy)

1995-12-31

368

A review of ultrabrief pulse width electroconvulsive therapy.  

UK PubMed Central (United Kingdom)

The effect of shortening the pulse width of the electrical stimulus when administering electroconvulsive therapy (ECT) has recently been systematically studied with promising results. This review examines reported outcomes from three randomized controlled trials which compared ultrabrief (?0.3 ms) with brief (0.5-1.5 ms) pulse width ECT, and other recent clinical trials of ultrabrief pulse width ECT. The emerging evidence for ultrabrief pulse right unilateral (RUL) ECT suggests clinically meaningful efficacy and substantially reduced neuropsychological side effects compared with standard (brief) pulse ECT; this may represent a generational advance in the ECT technique. However, it is unclear if patients receiving ultrabrief pulse RUL ECT may have a slower speed of response and require additional treatments compared with brief pulse ECT. Therefore, until further data are available, clinicians may be well advised to use brief pulse ECT in situations requiring an urgent clinical response. The evidence base for ultrabrief bilateral ECT is limited, with findings that efficacy may be reduced compared with brief pulse width ECT. Thus ultrabrief bilateral ECT should not be used outside the research setting.

Loo CK; Katalinic N; Martin D; Schweitzer I

2012-03-01

369

Hadron resonances, large Nc, and the half-width rule  

CERN Document Server

We suggest using the half-width rule to make an estimate of the 1/Nc errors in hadronic models containing resonances. We show simple consequences ranging from the analysis of meson Regge trajectories, the hadron resonance gas at finite temperature and generalized hadronic form factors.

Arriola, Enrique Ruiz; Masjuan, Pere

2012-01-01

370

Widths of the atomic K-N7 levels  

CERN Document Server

Atomic level widths obtained from experimental measurements are collected in Table I, along with the corresponding theoretical widths derived from the Evaluated Atomic Data Library (EADL) of Lawrence Livermore National Laboratory; these EADL values are based upon the Dirac-Hartree-Slater version of the independent-particle model. In a minority of cases, many-body theory predictions are also provided. A brief discussion of the manner in which the experimental widths were deduced from spectroscopic data is included. The bulk of the data are for elements in the solid state, but a few data for gases and simple compounds are included. For the K, L2, L3, and M5 levels, where Coster-Kronig contributions do not contribute or contribute only to a small extent to the overall widths, the EADL predictions appear satisfactory for elements in the solid state. For other levels, where Coster-Kronig and super-Coster-Kronig transitions have large probabilities within the independent-particle model, this model is not satisfacto...

Campbell, J L

2001-01-01

371

FLEXIBLE TUBE WITH CIRCULAR GROOVES OF VARYING WIDTH AND DEPTH  

UK PubMed Central (United Kingdom)

A flexible lumen (10, 10', 10'', 110, 210) made from a solid, relatively rigid tubing (12, 12', 12'', 112, 212) that is made flexible by cutting a series of grooves (14, 14', 14'', 114, 214) of varying width and depth through the side of the tubing (12, 12', 12'', 112, 212).

INJEV Valentine P.

372

Dynamical Screening of Atom Confined by Finite-Width Fullerene  

CERN Document Server

This is an investigation on the dynamical screening of an atom confined within a fullerene of finite width. The two surfaces of the fullerene lead to the presence of two surface plasmon eigenmodes. It is shown that, in the vicinity of these two eigenfrequencies, there is a large enhancement of the confined atom's photoabsorption rate.

Lo, S; Solovyov, A V

2007-01-01

373

A review of ultrabrief pulse width electroconvulsive therapy  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The effect of shortening the pulse width of the electrical stimulus when administering electroconvulsive therapy (ECT) has recently been systematically studied with promising results. This review examines reported outcomes from three randomized controlled trials which compared ultrabrief (?0.3 ms) w...

Loo, Colleen K.; Katalinic, Natalie; Martin, Donel; Schweitzer, Isaac

374

On the definition of the \\Delta mass and width  

CERN Multimedia

In the framework of effective field theory we show that, at two-loop order, the mass and width of the \\Delta resonance defined via the (relativistic) Breit-Wigner parametrization both depend on the choice of field variables. In contrast, the complex-valued position of the pole of the propagator is independent of this choice.

Djukanovic, D; Scherer, S

2007-01-01

375

Finite-width effects in the mixing of neutral mesons  

CERN Document Server

We analyze a contribution of the finite-width (mass-smearing) effects to the mixing of neutral mesons. It was shown, that this contribution is dominant in the D-meson system and large in the K-meson one. An account of the mass-smearing effects allows to explain some discrepancy between standard predictions and experimental data in these cases.

Kuksa, V I

2009-01-01

376

Width of the Darwin table for forbidden reflexes  

International Nuclear Information System (INIS)

It is shown that reflexes with form factor equal to zero are not absent, but have very small Darwin table width, which is determined by shift of the Bragg point and by form factors of another type. It is pointed out that this effect cannot be obtained within Ewald theory of dynamical diffraction on single crystals. 9 refs

1996-01-01

377

Direct top-quark width measurement at CDF.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We present a measurement of the top-quark width in the lepton+jets decay channel of tt events produced in p p collisions at Fermilab's Tevatron collider and collected by the CDF II detector. From a data sample corresponding to 4.3 fb(-1) of integrated luminosity, we identify 756 candidate events. Th...

Aaltonen, T; Álvarez González, B; Amerio, S; Amidei, D; Anastassov, A

378

Improved determination of the width of the top quark  

Energy Technology Data Exchange (ETDEWEB)

We present an improved determination of the total width of the top quark, {Gamma}{sub t}, using 5.4 fb{sup -1} of integrated luminosity collected by the D0 Collaboration at the Tevatron p{bar p} Collider. The total width {Gamma}{sub t} is extracted from the partial decay width {Gamma}(t {yields} Wb) and the branching fraction {Beta}(t {yields} Wb). {Gamma}(t {yields} Wb) is obtained from the t-channel single top-quark production cross section and {Beta}(t {yields} Wb) is measured in t{bar t} events. For a top mass of 172.5 GeV, the resulting width is {Gamma}{sub t} = 2.00{sub -0.43}{sup +0.47} GeV. This translates to a top-quark lifetime of {tau}{sub t} = (3.29{sub -0.63}{sup +0.90}) x 10{sup -25} s. We also extract an improved direct limit on the Cabibbo-Kobayashi-Maskawa quark-mixing matrix element 0.81 < |V{sub tb}| {le} 1 at 95% C.L. and a limit of |V{sub tb}| < 0.59 for a high-mass fourth-generation bottom quark assuming unitarity of the fourth-generation quark-mixing matrix.

Abazov V. M.; Abbott B.; Acharya B. S.; Adams M.; Adams T.; Alexeev G. D.; Alkhazov G.; Alton A.; Alverson G.; Aoki M.; Askew A.; Asman B.; Atkins S.; Atramentov O.; Augsten K.; Avila C.; BackusMayes J.; Badaud F.; Bagby L.; Baldin B.; Bandurin D. V.; Banerjee S.; Barberis E.; Baringer P.; Barreto J.; Bartlett J. F.; Bassler U.; Bazterra V.; Bean A.; Begalli M.; Belanger-Champagne C.; Bellantoni L.; Beri S. B.; Bernardi G.; Bernhard R.; Bertram I.; Besancon M.; Beuselinck R.; Bezzubov V. A.; Bhat P. C.; Bhatia S.; Bhatnagar V.; Blazey G.; Blessing S.; Bloom K.; Boehnlein A.; Boline D.; Boos E. E.; Borissov G.; Bose T.; Brandt A.; Brandt O.; Brock R.; Brooijmans G.; Bross A.; Brown D.; Brown J.; Bu X. B.; Buehler M.; Buescher V.; Bunichev V.; Burdin S.; Burnett T. H.; Buszello C. P.; Calpas B.; Camacho-Perez E.; Carrasco-Lizarraga M. A.; Casey C. K.; Castilla-Valdez H.; Chakrabarti S.; Chakraborty D.; Chan M.; Chandra A.; Chapon E.; Chen G.; Chevalier-Thery S.; Cho D. K.; Cho S. W.; Choi S.; Choudhary B.; Cihangir S.; Claes D.; Clutter J.; Cooke M.; Cooper W. E.; Corcoran M.; Couderc F.; Cousinou M. -C.; Croc A.; Cutts D.; Das A.; Davies G.; de Jong S. J.; De La Cruz-Burelo E.; Deliot F.; Demina R.; Denisov D.; Denisov S. P.; Desai S.; Deterre C.; DeVaughan K.; Diehl H. T.; Diesburg M.; Ding P. F.; Dominguez A.; Dorland T.; Dubey A.; Dudko L. V.; Duggan D.; Duperrin A.; Dutt S.; Dyshkant A.; Eads M.; Edmunds D.; Ellison J.; Elvira V. D.; Enari Y.; Evans H.; Evdokimov A.; Evdokimov V. N.; Facini G.; Ferbel T.; Fiedler F.; Filthaut F.; Fisher W.; Fisk H. E.; Fortner M.; Fox H.; Fuess S.; Garcia-Bellido A.; Garcia-Guerra G. A.; Gavrilov V.; Gay P.; Geng W.; Gerbaudo D.; Gerber C. E.; Gershtein Y.; Ginther G.; Golovanov G.; Goussiou A.; Graf C. P.; Grannis P. D.; Greder S.; Greenlee H.; Greenwood Z. D.; Gregores E. M.; Grenier G.; Gris Ph.; Grivaz J. -F.; Grohsjean A.; Gruenendahl S.; Gruenewald M. W.; Guillemin T.; Gutierrez G.; Gutierrez P.; Haas A.; Hagopian S.; Haley J.; Han L.; Harder K.; Harel A.; Hauptman J. M.; Hays J.; Head T.; Hebbeker T.; Hedin D.; Hegab H.; Heinson A. P.; Heintz U.; Hensel C.; La Cruz I. Heredia-De; Herner K.; Hesketh G.; Hildreth M. D.; Hirosky R.; Hoang T.; Hobbs J. D.; Hoeneisen B.; Hohlfeld M.; Hubacek Z.; Hynek V.; Iashvili I.; Ilchenko Y.; Illingworth R.; Ito A. S.; Jabeen S.; Jaffre M.; Jamin D.; Jayasinghe A.; Jesik R.; Johns K.; Johnson M.; Jonckheere A.; Jonsson P.; Joshi J.; Jung A. W.; Juste A.; Kaadze K.; Kajfasz E.; Karmanov D.; Kasper P. A.; Katsanos I.; Kehoe R.; Kermiche S.; Khalatyan N.; Khanov A.; Kharchilava A.; Kharzheev Y. N.; Kohli J. M.; Kozelov A. V.; Kraus J.; Kulikov S.; Kumar A.; Kupco A.; Kurca T.; Kuzmin V. A.; Lammers S.; Landsberg G.; Lebrun P.; Lee H. S.; Lee S. W.; Lee W. M.; Lellouch J.; Li H.; Li L.; Li Q. Z.; Lietti S. M.; Lim J. K.; Lincoln D.; Linnemann J.; Lipaev V. V.; Lipton R.; Liu Y.; Lobodenko A.; Lokajicek M.; de Sa R. Lopes; Lubatti H. J.; Luna-Garcia R.; Lyon A. L.; Maciel A. K. A.; Mackin D.; Madar R.; Magana-Villalba R.; Malik S.; Malyshev V. L.; Maravin Y.; Martinez-Ortega J.; McCarthy R.; McGivern C. L.; Meijer M. M.; Melnitchouk A.; Menezes D.; Mercadante P. G.; Merkin M.; et al.

2012-05-04

379

Model-potential method for computation of autoionization state widths  

International Nuclear Information System (INIS)

The model-potential method (MPM), previously developed for describing single-electron excitations, is generalized to the case of two-electron transitions in atoms. A method is proposed for computing autoionization state widths with the help of the MPM, and the autoionization probabilities of He and Li atoms are calculated

1982-01-01

380

Porous Alumina Films with Width-Controllable Alumina Stripes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the ...

Huang, Kai; Huang, Shi-Ming; Pu, Lin; Shi, Yi; Wu, Zhi-Ming; Ji, Li; Kang, Jun-Yong

 
 
 
 
381

Sinusoidal and Space Vector Pulse Width Modulation for Inverter  

Directory of Open Access Journals (Sweden)

Full Text Available Inverters inherently have the property of controlling output frequency but the output voltage can’t be varied. Usually to vary output voltage we have to vary supply voltage which is not always possible for this reason PWM techniques gained momentum. Basic aim of PWM technique is to control output voltage and harmonic reduction. Pulse-width modulation (PWM), or pulseduration modulation (PDM), is a commonly used technique for controlling power to inertial electrical devices, made practical by modern electronic power switches. Here we apply PWM techniques like Sinusoidal pulse width modulation (SPWM) and Space Vector Pulse width Modulation (SVPWM) to inverter and study its performance. In Sinusoidal Pulse width modulation (SPWM) we generate the gating signals by comparing a sinusoidal reference signal with a triangular carrier wave. In Space vector Modulation (SVPWM) we consider a rotating phased which is obtained by adding all the three voltages. Modulation is accomplished by switching state of an inverter. Thus by comparing these two techniques we study the performance of our inverter.

K. Mounika#1 , B. Kiran Babu

2013-01-01

382

Effect of magnetic perturbations on divertor scrape-off width  

International Nuclear Information System (INIS)

[en] A general method is developed for calculating the width, due to magnetic perturbations, of the scrape-off layer of a tokamak with a divertor. The general method is applied to a simple analytic model of a divertor to indicate the magnitude of the effects that would be expected

1977-01-01

383

Revision of the Ontario phenylalanine equivalency system and development of a low protein equivalency system.  

UK PubMed Central (United Kingdom)

The Phenylalanine Content of Foods, an equivalency system used in the dietary treatment of phenylketonuria, was prepared in 1975. Recently this system was revised to include a total of 372 food items in various raw and processed states. Food lists are available in a simple version for parents listing the serving size per phenylalanine equivalent, and in a more comprehensive version for dietitians providing weights for the serving sizes as well as values for phenylalanine, protein, and energy per equivalent. Subsequently, the system was modified to form a low protein equivalency system for use in designing low protein diets for a number of other inherited metabolic disorders.

Chan L; Bell L; Hanley WB

1982-10-01

384

Equivalence and Isomorphism for Boolean Constraint Satisfaction  

CERN Multimedia

A Boolean constraint satisfaction instance is a conjunction of constraint applications, where the allowed constraints are drawn from a fixed set B of Boolean functions. We consider the problem of determining whether two given constraint satisfaction instances are equivalent and prove a Dichotomy Theorem by showing that for all sets C of allowed constraints, this problem is either polynomial-time solvable or coNP-complete, and we give a simple criterion to determine which case holds. A more general problem addressed in this paper is the isomorphism problem, the problem of determining whether there exists a renaming of the variables that makes two given constraint satisfaction instances equivalent in the above sense. We prove that this problem is coNP-hard if the corresponding equivalence problem is coNP-hard, and polynomial-time many-one reducible to the graph isomorphism problem in all other cases.

Böhler, E; Reith, S; Vollmer, H; Reith, Steffen; Vollmer, Heribert

2002-01-01

385

On the Equivalence of Quadratic APN Functions  

CERN Multimedia

Establishing the CCZ-equivalence of a pair of APN functions is generally quite difficult. In some cases, when seeking to show that a putative new infinite family of APN functions is CCZ inequivalent to an already known family, we rely on computer calculation for small values of n. In this paper we present a method to prove the inequivalence of quadratic APN functions with the Gold functions. Our main result is that a quadratic function is CCZ-equivalent to an APN Gold function if and only if it is EA-equivalent to that Gold function. As an application of this result, we prove that a trinomial family of APN functions that exist on finite fields of order 2^n where n = 2 mod 4 are CCZ inequivalent to the Gold functions. The proof relies on some knowledge of the automorphism group of a code associated with such a function.

Byrne, Eimear; McGuire, Gary; Nebe, Gabriele

2011-01-01

386

Topological equivalence of nonlinear autonomous dynamical systems  

International Nuclear Information System (INIS)

We show in this paper that the autonomous nonlinear dynamical system ?(A,B,F): x' = Ax+Bu+F(x) is topologically equivalent to the linear dynamical system ?(A,B,O): x' = Ax+Bu if the projection of A on the complement in Rn of the controllable vectorial subspace is hyperbolic and if lipschitz constant of F is sufficiently small (*) and F(x) = 0 when parallel x parallel is sufficiently large (**). In particular, if ?(A,B,O) is controllable, it is topologically equivalent to ?(A,B,F) when it is only that F satisfy (**). (author). 18 refs.

1995-01-01

387

Equivalent circuit model of radiative heat transfer  

CERN Document Server

Here, we develop a theory of radiative heat transfer based on an equivalent electrical network representation for the hot material slabs in an arbitrary multilayered environment with arbitrary distribution of temperatures and electromagnetic properties among the layers. Our approach is fully equivalent to the known theories operating with the fluctuating current density, while being significantly simpler in analysis and applications. A practical example of the near-infrared heat transfer through the micron gap filled with an indefinite metmaterial is considered using the suggested method. The giant enhancement of the transferred heat compared to the case of the empty gap is shown.

Maslovski, Stanislav I; Tretyakov, Sergei A

2012-01-01

388

Measurements of neutron dose equivalent for a proton therapy center using uniform scanning proton beams  

Energy Technology Data Exchange (ETDEWEB)

Purpose: Neutron exposure is of concern in proton therapy, and varies with beam delivery technique, nozzle design, and treatment conditions. Uniform scanning is an emerging treatment technique in proton therapy, but neutron exposure for this technique has not been fully studied. The purpose of this study is to investigate the neutron dose equivalent per therapeutic dose, H/D, under various treatment conditions for uniform scanning beams employed at our proton therapy center. Methods: Using a wide energy neutron dose equivalent detector (SWENDI-II, ThermoScientific, MA), the authors measured H/D at 50 cm lateral to the isocenter as a function of proton range, modulation width, beam scanning area, collimated field size, and snout position. They also studied the influence of other factors on neutron dose equivalent, such as aperture material, the presence of a compensator, and measurement locations. They measured H/D for various treatment sites using patient-specific treatment parameters. Finally, they compared H/D values for various beam delivery techniques at various facilities under similar conditions. Results: H/D increased rapidly with proton range and modulation width, varying from about 0.2 mSv/Gy for a 5 cm range and 2 cm modulation width beam to 2.7 mSv/Gy for a 30 cm range and 30 cm modulation width beam when 18 Multiplication-Sign 18 cm{sup 2} uniform scanning beams were used. H/D increased linearly with the beam scanning area, and decreased slowly with aperture size and snout retraction. The presence of a compensator reduced the H/D slightly compared with that without a compensator present. Aperture material and compensator material also have an influence on neutron dose equivalent, but the influence is relatively small. H/D varied from about 0.5 mSv/Gy for a brain tumor treatment to about 3.5 mSv/Gy for a pelvic case. Conclusions: This study presents H/D as a function of various treatment parameters for uniform scanning proton beams. For similar treatment conditions, the H/D value per uncollimated beam size for uniform scanning beams was slightly lower than that from a passive scattering beam and higher than that from a pencil beam scanning beam, within a factor of 2. Minimizing beam scanning area could effectively reduce neutron dose equivalent for uniform scanning beams, down to the level close to pencil beam scanning.

Zheng Yuanshui; Liu Yaxi; Zeidan, Omar; Schreuder, Andries Niek; Keole, Sameer [ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); INTEGRIS Cancer Insititute, 5911 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); ProCure Treatment Centers, 420 North Walnut Street, Bloomington, Indiana 47404 (United States); ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States)

2012-06-15

389

Determination of equivalent weight of amines  

Energy Technology Data Exchange (ETDEWEB)

A procedure for the determination of equivalent weight of amines is described. This procedure is based on an acid-base reaction performed in glacial acetic acid. The sum of primary, secondary, and tertiary amines are determined by titration with standard perchloric acid in glacial acetic acid. 1 ref.

Selig, W.S.

1987-01-08

390

Reading adn Auditory-Visual Equivalences  

Science.gov (United States)

|A retarded boy, unable to read orally or with comprehension, was taught to match spoken to printed words and was then capable of reading comprehension (matching printed words to picture) and oral reading (naming printed words aloud), demonstrating that certain learned auditory-visual equivalences are sufficient prerequisites for reading…

Sidman, Murray

1971-01-01

391

Canonical equivalence between massive spin 1 theories  

CERN Multimedia

The model of Cremmer-Scherck and Proca are considered in dimensions greater than 3+1. It is obtained that the Proca model correspond to a gauged fixed version of the Cremmer-Scherck one, and we show their canonical equivalence.

Arias, P J; Arias, Pio J.; Perez-Mosquera, Jean C.

2004-01-01

392

Unitary equivalence to truncated Toeplitz operators  

CERN Document Server

In this paper we investigate operators unitarily equivalent to truncated Toeplitz operators. We show that this class contains certain sums of tensor products of truncated Toeplitz operators. In particular, it contains arbitrary inflations of truncated Toeplitz operators; this answers a question posed by Cima, Garcia, Ross, and Wogen.

Strouse, Elizabeth; Zarrabi, Mohamed

2010-01-01

393

Skin equivalent produced with human collagen.  

Science.gov (United States)

Several studies have recently been conducted on cultured skin equivalent (SE), prepared using human keratinocytes seeded on various types of dermal equivalents (DE). We previously showed the advantages of our anchorage method in preventing the severe surface reduction of DE due to fibroblast contractile properties in vitro. A new anchored human SE was established in our laboratory in order to obtain a bioengineered tissue that would possess the appropriate histological and biological properties. In order to compare the effects of different collagen origins on the evolution of SE in vitro, human keratinocytes were seeded on three types of anchored DE. A comparative study was carried out between bovine SE (bSE), human SE (hSE), and human skin equivalent containing additional dermal matrix components (hSE+). Immunohistological analysis showed that hSE and hSE+ presented good structural organization, including the deposition of several basement membrane constituents. Higher amounts of transglutaminase, ceramides, and keratin 1 were detected in the epidermal layers of all SE when cultured at the air-liquid interface. However, a 92 kDa gelatinase activity was higher in bovine skin equivalent (bSE) compared to hSE cultures. The use of human collagens comparatively to bovine collagen as SE matricial component delayed the degradation of the dermal layer in culture. PMID:8589886

Auger, F A; López Valle, C A; Guignard, R; Tremblay, N; Noël, B; Goulet, F; Germain, L

1995-06-01

394

Skin equivalent produced with human collagen.  

UK PubMed Central (United Kingdom)

Several studies have recently been conducted on cultured skin equivalent (SE), prepared using human keratinocytes seeded on various types of dermal equivalents (DE). We previously showed the advantages of our anchorage method in preventing the severe surface reduction of DE due to fibroblast contractile properties in vitro. A new anchored human SE was established in our laboratory in order to obtain a bioengineered tissue that would possess the appropriate histological and biological properties. In order to compare the effects of different collagen origins on the evolution of SE in vitro, human keratinocytes were seeded on three types of anchored DE. A comparative study was carried out between bovine SE (bSE), human SE (hSE), and human skin equivalent containing additional dermal matrix components (hSE+). Immunohistological analysis showed that hSE and hSE+ presented good structural organization, including the deposition of several basement membrane constituents. Higher amounts of transglutaminase, ceramides, and keratin 1 were detected in the epidermal layers of all SE when cultured at the air-liquid interface. However, a 92 kDa gelatinase activity was higher in bovine skin equivalent (bSE) compared to hSE cultures. The use of human collagens comparatively to bovine collagen as SE matricial component delayed the degradation of the dermal layer in culture.

Auger FA; López Valle CA; Guignard R; Tremblay N; Noël B; Goulet F; Germain L

1995-06-01

395

Equivalent martingale measures and Lévy processes  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper we compute equivalent martingale measures when the asset price returns are modelled by a Lévy process. We follow the approach introduced by Gerber and Shiu (1994).Neste trabalho calculamos as medidas martingalas equivalentes quando os retornos dos preços dos ativos são modelados por um Processo de Lévy. Seguimos a formulação introduzida por Gerber and Shiu (1994).

José Santiago Fajardo

2006-01-01

396

Solving Electromagnetic Boundary Problems with Equivalence Methods  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A basic problem in electromagnetics involves solving the Maxwell equations in a non-empty space, i.e. in a space with interfaces or boundaries. In this dissertation the wanted electromagnetic fields are searched via equivalence methods: a full electromagnetic problem is transformed to a simpler solv...

Hänninen, Jari J.

397

Decidability, Behavioural Equivalences and Infinite Transition Graphs  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This thesis studies behavioural equivalences on labelled infinite transition graphs and the role that they can play in the context of modal logics and notions from language theory. A natural class of such infinite graphs is that corresponding to the SnS-definable tree languages first studied by Rabi...

Hüttel, Hans

398

Equivalent Circuit Modeling of Hysteresis Motors.  

Science.gov (United States)

We performed a literature review and found that many equivalent circuit models of hysteresis motors in use today are incorrect. The model by Miyairi and Kataoka (1965) is the correct one. We extended the model by transforming it to quadrature coordinates,...

B. A. Kirkendall E. T. Scharlemann J. J. Nitao

2009-01-01

399

The Equivalence of Giuga's and Agoh's Conjectures  

CERN Multimedia

In this paper we show the equivalence of the conjectures of Giuga and Agoh in a direct way which leads to a combined conjecture. This conjecture is described by a sum of fractions from which all conditions can be derived easily.

Kellner, B C

2004-01-01

400

Determination of the width of the top quark.  

UK PubMed Central (United Kingdom)

We extract the total width of the top quark, ?(t), from the partial decay width ?(t ? Wb) measured using the t-channel cross section for single top-quark production and from the branching fraction B(t ? Wb) measured in tt events using up to 2.3??fb(-1) of integrated luminosity collected by the D0 Collaboration at the Tevatron pp Collider. The result is ?(t) = 1.99(-0.55)(+0.69)??GeV, which translates to a top-quark lifetime of ?(t) = (3.3(-0.9)(+1.3)) × 10(-25) ??s. Assuming a high mass fourth generation b' quark and unitarity of the four-generation quark-mixing matrix, we set the first upper limit on |V(tb')| < 0.63 at 95% C.L.

Abazov VM; Abbott B; Abolins M; Acharya BS; Adams M; Adams T; Alexeev GD; Alkhazov G; Alton A; Alverson G; Alves GA; Ancu LS; Aoki M; Arnoud Y; Arov M; Askew A; Åsman B; Atramentov O; Avila C; BackusMayes J; Badaud F; Bagby L; Baldin B; Bandurin DV; Banerjee S; Barberis E; Baringer P; Barreto J; Bartlett JF; Bassler U; Bazterra V; Beale S; Bean A; Begalli M; Begel M; Belanger-Champagne C; Bellantoni L; Beri SB; Bernardi G; Bernhard R; Bertram I; Besançon M; Beuselinck R; Bezzubov VA; Bhat PC; Bhatnagar V; Blazey G; Blessing S; Bloom K; Boehnlein A; Boline D; Bolton TA; Boos EE; Borissov G; Bose T; Brandt A; Brandt O; Brock R; Brooijmans G; Bross A; Brown D; Brown J; Bu XB; Buchholz D; Buehler M; Buescher V; Bunichev V; Burdin S; Burnett TH; Buszello CP; Calpas B; Camacho-Pérez E; Carrasco-Lizarraga MA; Casey BC; Castilla-Valdez H; Chakrabarti S; Chakraborty D; Chan KM; Chandra A; Chen G; Chevalier-Théry S; Cho DK; Cho SW; Choi S; Choudhary B; Christoudias T; Cihangir S; Claes D; Clutter J; Cooke M; Cooper WE; Corcoran M; Couderc F; Cousinou MC; Croc A; Cutts D; ?wiok M; Das A; Davies G; De K; de Jong SJ; De la Cruz-Burelo E; Déliot F; Demarteau M; Demina R; Denisov D; Denisov SP; Desai S; DeVaughan K; Diehl HT; Diesburg M; Dominguez A; Dorland T; Dubey A; Dudko LV; Duggan D; Duperrin A; Dutt S; Dyshkant A; Eads M; Edmunds D; Ellison J; Elvira VD; Enari Y; Eno S; Evans H; Evdokimov A; Evdokimov VN; Facini G; Ferbel T; Fiedler F; Filthaut F; Fisher W; Fisk HE; Fortner M; Fox H; Fuess S; Gadfort T; Garcia-Bellido A; Gavrilov V; Gay P; Geist W; Geng W; Gerbaudo D; Gerber CE; Gershtein Y; Ginther G; Golovanov G; Goussiou A; Grannis PD; Greder S; Greenlee H; Greenwood ZD; Gregores EM; Grenier G; Gris P; Grivaz JF; Grohsjean A; Grünendahl S; Grünewald MW; Guo F; Guo J; Gutierrez G; Gutierrez P; Haas A; Hagopian S; Haley J; Han L; Harder K; Harel A; Hauptman JM; Hays J; Head T; Hebbeker T; Hedin D; Hegab H; Heinson AP; Heintz U; Hensel C; Heredia-De la Cruz I; Herner K; Hesketh G; Hildreth MD; Hirosky R; Hoang T; Hobbs JD; Hoeneisen B; Hohlfeld M; Hossain S; Hubacek Z; Huske N; Hynek V; Iashvili I; Illingworth R; Ito AS; Jabeen S; Jaffré M; Jain S; Jamin D; Jesik R; Johns K; Johnson M; Johnston D; Jonckheere A; Jonsson P; Joshi J; Juste A; Kaadze K; Kajfasz E; Karmanov D; Kasper PA; Katsanos I; Kehoe R; Kermiche S; Khalatyan N; Khanov A; Kharchilava A; Kharzheev YN; Khatidze D; Kirby MH; Kohli JM; Kozelov AV; Kraus J; Kumar A; Kupco A; Kur?a T; Kuzmin VA; Kvita J; Lammers S; Landsberg G; Lebrun P; Lee HS; Lee SW; Lee WM; Lellouch J; Li L; Li QZ; Lietti SM; Lim JK; Lincoln D; Linnemann J; Lipaev VV; Lipton R; Liu Y; Liu Z; Lobodenko A; Lokajicek M; Love P; Lubatti HJ; Luna-Garcia R; Lyon AL; Maciel AK; Mackin D; Madar R; Magaña-Villalba R; Malik S; Malyshev VL; Maravin Y; Martínez-Ortega J; McCarthy R; McGivern CL; Meijer MM; Melnitchouk A; Menezes D; Mercadante PG; Merkin M; Meyer A; Meyer J; Mondal NK; Muanza GS; Mulhearn M; Nagy E; Naimuddin M; Narain M; Nayyar R; Neal HA; Negret JP; Neustroev P; Novaes SF; Nunnemann T; Obrant G; Orduna J; Osman N; Osta J; Otero y Garzón GJ; Owen M; Padilla M; Pangilinan M; Parashar N; Parihar V; Park SK; Parsons J; Partridge R; Parua N; Patwa A; Penning B; Perfilov M; Peters K; Peters Y; Petrillo G; Pétroff P; Piegaia R; Piper J; Pleier MA; Podesta-Lerma PL; Podstavkov VM; Pol ME; Polozov P; Popov AV; Prewitt M; Price D; Protopopescu S; Qian J; Quadt A; Quinn B; Rangel MS; Ranjan K; Ratoff PN; Razumov I; Renkel P; Rich P; Rijssenbeek M; Ripp-Baudot I; Rizatdinova F; Rominsky M; Royon C; Rubinov P; Ruchti R; Safronov G; Sajot G; Sánchez-Hernández A; Sanders MP; Sanghi B; Santos AS; Savage G; Sawyer L; Scanlon T; Schamberger RD; Scheglov Y; Schellman H; Schliephake T; Schlobohm S; Schwanenberger C; Schwienhorst R; Sekaric J; Severini H; Shabalina E; Shary V; Shchukin AA; Shivpuri RK; Simak V; Sirotenko V; Skubic P; Slattery P; Smirnov D; Smith KJ; Snow GR; Snow J; Snyder S; Söldner-Rembold S; Sonnenschein L; Sopczak A; Sosebee M; Soustruznik K; Spurlock B; Stark J; Stolin V; Stoyanova DA; Strauss E; Strauss M; Strom D; Stutte L; Svoisky P; Takahashi M; Tanasijczuk A; Taylor W; Titov M; Tokmenin VV; Tsybychev D; Tuchming B; Tully C; Tuts PM; Uvarov L; Uvarov S; Uzunyan S; Van Kooten R; van Leeuwen WM; Varelas N; Varnes EW; Vasilyev IA; Verdier P; Vertogradov LS; Verzocchi M; Vesterinen M; Vilanova D; Vint P; Vokac P; Wahl HD; Wang MH; Warchol J; Watts G; Wayne M; Weber M; Welty-Rieger L; Wetstein M; White A; Wicke D; Williams MR; Wilson GW; Wimpenny SJ; Wobisch M; Wood DR; Wyatt TR; Xie Y; Xu C; Yacoob S; Yamada R; Yang WC; Yasuda T; Yatsunenko YA; Ye Z; Yin H; Yip K; Yoo HD; Youn SW; Yu J; Zelitch S; Zhao T; Zhou B; Zhu J; Zielinski M; Zieminska D; Zivkovic L

2011-01-01

 
 
 
 
401

Determination of the Width of the Top Quark  

International Nuclear Information System (INIS)

We extract the total width of the top quark, ?t, from the partial decay width ?(t?Wb) measured using the t-channel cross section for single top-quark production and from the branching fraction B(t?Wb) measured in tt events using up to 2.3 fb-1 of integrated luminosity collected by the D0 Collaboration at the Tevatron pp Collider. The result is ?t=1.99-0.55+0.69 GeV, which translates to a top-quark lifetime of ?t=(3.3-0.9+1.3)x10-25 s. Assuming a high mass fourth generation b' quark and unitarity of the four-generation quark-mixing matrix, we set the first upper limit on |Vtb'|

2011-01-14

402

Determination of the width of the top quark.  

Science.gov (United States)

We extract the total width of the top quark, ?(t), from the partial decay width ?(t ? Wb) measured using the t-channel cross section for single top-quark production and from the branching fraction B(t ? Wb) measured in tt events using up to 2.3??fb(-1) of integrated luminosity collected by the D0 Collaboration at the Tevatron pp Collider. The result is ?(t) = 1.99(-0.55)(+0.69)??GeV, which translates to a top-quark lifetime of ?(t) = (3.3(-0.9)(+1.3)) × 10(-25) ??s. Assuming a high mass fourth generation b' quark and unitarity of the four-generation quark-mixing matrix, we set the first upper limit on |V(tb')| < 0.63 at 95% C.L. PMID:21405220

Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Ancu, L S; Aoki, M; Arnoud, Y; Arov, M; Askew, A; Åsman, B; Atramentov, O; Avila, C; BackusMayes, J; Badaud, F; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Barberis, E; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bazterra, V; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Blazey, G; Blessing, S; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brandt, O; Brock, R; Brooijmans, G; Bross, A; Brown, D; Brown, J; Bu, X B; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burnett, T H; Buszello, C P; Calpas, B; Camacho-Pérez, E; Carrasco-Lizarraga, M A; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chen, G; Chevalier-Théry, S; Cho, D K; Cho, S W; Choi, S; Choudhary, B; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Croc, A; Cutts, D; ?wiok, M; Das, A; Davies, G; De, K; de Jong, S J; De la Cruz-Burelo, E; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; DeVaughan, K; Diehl, H T; Diesburg, M; Dominguez, A; Dorland, T; Dubey, A; Dudko, L V; Duggan, D; Duperrin, A; Dutt, S; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Evans, H; Evdokimov, A; Evdokimov, V N; Facini, G; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fuess, S; Gadfort, T; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Geng, W; Gerbaudo, D; Gerber, C E; Gershtein, Y; Ginther, G; Golovanov, G; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Hagopian, S; Haley, J; Han, L; Harder, K; Harel, A; Hauptman, J M; Hays, J; Head, T; Hebbeker, T; Hedin, D; Hegab, H; Heinson, A P; Heintz, U; Hensel, C; Heredia-De la Cruz, I; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hossain, S; Hubacek, Z; Huske, N; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jamin, D; Jesik, R; Johns, K; Johnson, M; Johnston, D; Jonckheere, A; Jonsson, P; Joshi, J; Juste, A; Kaadze, K; Kajfasz, E; Karmanov, D; Kasper, P A; Katsanos, I; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Khatidze, D; Kirby, M H; Kohli, J M; Kozelov, A V; Kraus, J; Kumar, A; Kupco, A; Kur?a, T; Kuzmin, V A; Kvita, J; Lammers, S; Landsberg, G; Lebrun, P; Lee, H S; Lee, S W; Lee, W M; Lellouch, J; Li, L; Li, Q Z; Lietti, S M; Lim, J K; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna-Garcia, R; Lyon, A L; Maciel, A K A; Mackin, D; Madar, R; Magaña-Villalba, R; Malik, S; Malyshev, V L; Maravin, Y; Martínez-Ortega, J; McCarthy, R; McGivern, C L; Meijer, M M; Melnitchouk, A; Menezes, D; Mercadante, P G; Merkin, M; Meyer, A; Meyer, J; Mondal, N K; Muanza, G S; Mulhearn, M; Nagy, E; Naimuddin, M; Narain, M; Nayyar, R; Neal, H A; Negret, J P; Neustroev, P; Novaes, S F; Nunnemann, T; Obrant, G; Orduna, J; Osman, N; Osta, J; Otero y Garzón, G J; Owen, M; Padilla, M; Pangilinan, M; Parashar, N; Parihar, V; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Penning, B; Perfilov, M; Peters, K; Peters, Y; Petrillo, G; Pétroff, P; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pol, M-E; Polozov, P; Popov, A V; Prewitt, M; Price, D; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rangel, M S; Ranjan, K; Ratoff, P N; Razumov, I; Renkel, P; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Sanghi, B; Santos, A S; Savage, G; Sawyer, L; Scanlon, T; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schlobohm, S; Schwanenberger, C; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shary, V; Shchukin, A A; Shivpuri, R K; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Smith, K J; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Spurlock, B; Stark, J; Stolin, V; Stoyanova, D A; Strauss, E; Strauss, M; Strom, D; Stutte, L; Svoisky, P; Takahashi, M; Tanasijczuk, A; Taylor, W; Titov, M; Tokmenin, V V; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Uvarov, L; Uvarov, S; Uzunyan, S; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Verdier, P; Vertogradov, L S

2011-01-11

403

???????? ????????????????? ?????????? ?????? ????????? ?????? ?????????????? ????????? Experimental research methodology crack opening width of reinforced concrete elements ???????? ????????????????? ????????????  

Directory of Open Access Journals (Sweden)

Full Text Available  ????????????? ?????? ????????????????? ?????????? ?????????? ?????? ????????? ?????? ?? ?????? ??????? ???????? ?? ??? ??????????? ?????????, ?????????? ???????? ? ?????? ? ??????????? ?????????????? ?????? ? ????? ?????????????? ????????. ????? ???????? ??? ????????? ?? ???????? ?????? ? ??????????? ????????????, ?????????  ??????????????? ??????? ????? ??????. ?????????? ???????? ????????????????? ?????????? ?????? ????????? ?????? ?????????????? ???????????. The tasks of experimental researches have been formulated, basic of which are: definition of width  disclosing  cracks at a level of the working fixture and in several levels above the stretched fixture; changes of distance between cracks and length of cracks in process of increase of loading with check of multilevel process of formation cracks; definition of deformations of the fixture and concrete with deformation account of effect in a vicinity of a two-console element. The technique of experimental researches of width of disclosing cracks of ferro-concrete designs from a position of the mechanics destruction is developed which has allowed to decide the put tasks. C????????????? ?????? ????????????????? ????????????, ??????????? ?????? ????????? ?????? ?? ??????? ??????? ???????? ? ??? ?????????? ?????????, ?????????? ???????? ? ?????? ? ?????? ??????????????? ??????? ? ??????????? ??????????????? ????????, ????????? ?????????? ????? ?????????  ? ????? ?????? ? ??????????? ????????, ???????? ??????????????? ???????? ??????????? ??????. ??????????? ???????? ????????????????? ???????????? ?????? ????????? ?????? ?????????????? ???????????.

?.?. ????????; ????? ??? ?????

2006-01-01

404

Z width and branching ratios in extended gauge models  

International Nuclear Information System (INIS)

In this paper, the authors study the effects of a possible new heavy neutral vector boson ZH on the partial and total widths of the ZL which are being studied at LEP. The analysis is formulated in as general terms as possible, without commitment to a particular model. The constraints on mzH from CDF and the new data on mw/mZL and mzL are taken into account. As expected, the induced deviations are at the level of a few percent. The allowed range decreases with increasing mL. The lepton widths and the peak cross-sections are particularly sensitive. A fourth light neutrino is excluded also in extended gauge models.

1990-01-01

405

The complexity of the fermionant, and immanants of constant width  

CERN Multimedia

In the context of statistical physics, Chandrasekharan and Wiese recently introduced the \\emph{fermionant} $\\Ferm_k$, a determinant-like quantity where each permutation $\\pi$ is weighted by $-k$ raised to the number of cycles in $\\pi$. We show that computing $\\Ferm_k$ is #P-hard under Turing reductions for any constant $k > 2$, and is $\\oplusP$-hard for $k=2$, even for the adjacency matrices of planar graphs. As a consequence, unless the polynomial hierarchy collapses, it is impossible to compute the immanant $\\Imm_\\lambda \\,A$ as a function of the Young diagram $\\lambda$ in polynomial time, even if the width of $\\lambda$ is restricted to be at most 2. In particular, if $\\Ferm_2$ is in P, or if $\\Imm_\\lambda$ is in P for all $\\lambda$ of width 2, then $\\NP \\subseteq \\RP$ and there are randomized polynomial-time algorithms for NP-complete problems.

Mertens, Stephan

2011-01-01

406

Width of Sunspot Generating Zone and Reconstruction of Butterfly Diagram  

CERN Document Server

Based on the extended Greenwich-NOAA/USAF catalogue of sunspot groups it is demonstrated that the parameters describing the latitudinal width of the sunspot generating zone (SGZ) are closely related to the current level of solar activity, and the growth of the activity leads to the expansion of SGZ. The ratio of the sunspot number to the width of SGZ shows saturation at a certain level of the sunspot number, and above this level the increase of the activity takes place mostly due to the expansion of SGZ. It is shown that the mean latitudes of sunspots can be reconstructed from the amplitudes of solar activity. Using the obtained relations and the group sunspot numbers by Hoyt and Schatten (1998), the latitude distribution of sunspot groups ("the Maunder butterfly diagram") for the 18th and the first half of the 19th centuries is reconstructed and compared with historical sunspot observations.

Ivanov, V G; 10.1007/s11207-010-9665-6

2010-01-01

407

Determination of the width of the top quark  

CERN Multimedia

We extract the total width of the top quark, Gamma_t, from the partial decay width Gamma(t -> W b) measured using the t-channel cross section for single top quark production and from the branching fraction B(t -> W b) measured in ttbar events using up to 2.3 fb^-1 of integrated luminosity collected by the D0 Collaboration at the Tevatron ppbar Collider. The result is Gamma_t = 1.99 +0.69 -0.55 GeV, which translates to a top-quark lifetime of tau_t = (3.3 +1.3 -0.9) x 10^-25 s. Assuming a high mass fourth generation b' quark and unitarity of the four-generation quark-mixing matrix, we set the first upper limit on |Vtb'| < 0.63 at 95% C.L.

Abazov, V M; Abolins, M; Acharya, B S; Adams, M; Adams, T; Alexeev, G D; Alkhazov, G; Altona, A; Alverson, G; Alves, G A; Ancu, L S; Aoki, M; Arnoud, Y; Arov, M; Askew, A; \\degAsman, B; Atramentov, O; Avila, C; BackusMayes, J; Badaud, F; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Barberis, E; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bazterra, V; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besan?con, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Blazey, G; Blessing, S; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brandt, O; Brock, R; Brooijmans, G; Bross, A; Brown, D; Brown, J; Bu, X B; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdinb, S; Burnett, T H; Buszello, C P; Calpas, B; Camacho-P?erez, E; Carrasco-Lizarraga, M A; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chen, G; Chevalier-Th?ery, S; Cho, D K; Cho, S W; Choi, S; Choudhary, B; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M -C; Croc, A; Cutts, D; ?Cwiok, M; Das, A; Davies, G; De, K; de Jong, S J; De La Cruz-Burelo, E; D?eliot, F; Demarteau, M; Demina, 47 R; Denisov, D; Denisov, S P; Desai, S; DeVaughan, K; Diehl, H T; Diesburg, M; Dominguez, A; Dorland, T; Dubey, A; Dudko, L V; Duggan, D; Duperrin, A; Dutt, S; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Evans, H; Evdokimov, A; Evdokimov, V N; Facini, G; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fuess, S; Gadfort, T; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Geng, W; Gerbaudo, D; Gerber, C E; Gershtein, Y; Ginther, G; Golovanov, G; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J -F; Grohsjean, A; Gr?unendahl, S; Gr?unewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haasc, A; Hagopian, S; Haley, J; Han, L; Harder, K; Harel, A; Hauptman, J M; Hays, J; Head, T; Hebbeker, T; Hedin, D; Hegab, H; Heinson, A P; Heintz, U; Hensel, C; La Cruz, I Heredia-De; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hossain, S; Hubacek, Z; Huske, N; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffr?e, M; Jain, S; Jamin, D; Jesik, R; Johns, K; Johnson, M; Johnston, D; Jonckheere, A; Jonsson, P; Joshi, J; Justed, A; Kaadze, K; Kajfasz, E; Karmanov, D; Kasper, P A; Katsanos, I; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Khatidze, D; Kirby, M H; Kohli, J M; Kozelov, A V; Kraus, J; Kumar, A; Kupco, A; Kur?ca, T; Kuzmin, V A; Kvita, J; Lammers, S; Landsberg, G; Lebrun, P; Lee, H S; Lee, S W; Lee, W M; Lellouch, J; Li, L; Li, Q Z; Lietti, S M; Lim, J K; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna-Garciae, R; Lyon, A L; Maciel, A K A; Mackin, D; Madar, R; Maga?na-Villalba, R; Malik, S; Malyshev, V L; Maravin, Y; Mart?\\inez-Ortega, J; McCarthy, R; McGivern, C L; Meijer, M M; Melnitchouk, A; Menezes, D; Mercadante, P G; Merkin, M; Meyer, A; Meyer, J; Mondal, N K; Muanza, G S; Mulhearn, M; Nagy, E; Naimuddin, M; Narain, M; Nayyar, R; Neal, H A; Negret, J P; Neustroev, P; Novaes, S F; Nunnemann, T; Obrant, G; Orduna, J; Osman, N; Osta, J; Garz?on, G J Otero y; Owen, 1 M; Padilla, M; Pangilinan, M; Parashar, N; Parihar, V; Park, S K; Parsons, J; Partridgec, R; Parua, N; Patwa, A; Penning, B; Perfilov, M; Peters, K; Peters, Y; Petrillo, G; P?etroff, P; Piegaia, R; Piper, J; Pleier, M -A; Podesta-Lermaf, P L M; Podstavkov, V M; Pol, M -E; Polozov, P; Popov, A V; Prewitt, M; Price, D; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rangel, M S; Ranjan, K; Ratoff, P N; Razumov, I; Renkel, P; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; S?anchez-Hern?andez, A; Sanders, M P; Sanghi, B; Santos, A S; Savage, G; Sawyer, L; Scanlon, T; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schlobohm, S; Schwanenberger, C; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shary, V; Shchukin, A A; Shivpuri, R K; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Smith, K J; Snow, G R; Snow, J; Snyder, S; S?oldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Spurlock, B; Stark, J; Stolin, V; Stoyanova, D A; Strauss, E; Strauss, M; Strom, D; Stutte, L; Svoisky, P; Takahashi, M; Tanasijczuk, A; Taylor, W; Titov, M; Tokmenin, V V; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Uvarov, L; Uzunyan, S Uvarov S; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Verdier, P

2010-01-01

408

The SOL width and the MHD interchange instability in tokamaks  

Energy Technology Data Exchange (ETDEWEB)

Instabilities in the SOL plasma can strongly influence the SOL plasma behaviour and in particular the SOL width. The SOL stability analysis shows that there exists a critical ratio of the thermal energy and the magnetic energy. If the SOL beta is greater than this critical value, the magnetic field cannot prevent the plasma displacement and a strong MHD instability in the SOL occurs. In the opposite case only slower resistive instabilities can develop. A theoretical investigation of the SOL plasma stability is presented for JET single-null and double-null divertor configurations. The dependence of the stability threshold on the SOL beta and on the sheath resistance is established. Applying a simple mixing length argument gives the scaling of the SOL width. 5 refs., 2 figs.

Kerner, W. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Pogutse, O. [Kurchatov institute, Moscow (Russian Federation)

1994-07-01

409

On the Angular Width of Diffractive Beam in Anisotropic Media  

CERN Document Server

2-D diffraction patterns arising in the far-field region were investigated theoretically for the case, when the plane wave with non collinear group and phase velocities is incident on the wide slit in opaque screen with arbitrary orientation. This investigation was carried out by consideration as an example of magnetostatic surface wave diffraction in tangentially magnetized ferrite slab. It was deduced the universal analytical formula, which one can use to calculate the angular width of diffractive beam in any 2-D anisotropic geometries for the waves of various nature. It was shown, that in 2-D anisotropic geometries this width may be not only more or less then the value L/D (L - wavelength of incident wave, D - length of slit), but it also may be equal to zero in certain conditions.

Lock, Edwin H

2011-01-01

410

Pole mass, width, and propagators of unstable fermions  

Energy Technology Data Exchange (ETDEWEB)

The concepts of pole mass and width are extended to unstable fermions in the general framework of parity-nonconserving gauge theories, such as the Standard Model. In contrast with the conventional on-shell definitions, these concepts are gauge independent and avoid severe unphysical singularities, properties of great importance since most fundamental fermions in nature are unstable particles. General expressions for the unrenormalized and renormalized dressed propagators of unstable fermions and their field-renormalization constants are presented. (orig.)

Kniehl, B.A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Sirlin, A. [New York Univ., NY (United States). Dept. of Physics

2008-01-15

411

Influence of Doppler Bin Width on GNSS Detection Probabilities  

CERN Multimedia

The acquisition stage in GNSS receivers determines Doppler shifts and code phases of visible satellites. Acquisition is thus a search in two continuous dimensions, where the digital algorithms require a partitioning of the search space into cells. We present analytic expressions for the acquisition performance depending on the partitioning of the Doppler frequency domain. In particular, the impact of the number and width of Doppler bins is analyzed. The presented results are verified by simulations.

Geiger, Bernhard C

2011-01-01

412

Total width of 125 GeV Higgs boson.  

UK PubMed Central (United Kingdom)

By using the LHC and Tevatron measurements of the cross sections to various decay channels relative to the standard model Higgs boson, the total width of the putative 125 GeV Higgs boson is determined as 6.1(-2.9)(+7.7) MeV. We describe a way to estimate the branching fraction for the Higgs-boson decay to dark matter. We also discuss a no-go theorem for the ?? signal of the Higgs boson at the LHC.

Barger V; Ishida M; Keung WY

2012-06-01

413

Two-body pionic-decay width of ??5H  

International Nuclear Information System (INIS)

The two-body pionic weak-decay of ??5H is investigated to see the feasibility of the double-? nuclear identification by using monoenergetic decay pions. The obtained width is 0.459 ??, and the branching ratio of the two-body decay to the total decay is estimated to be about 25%. Differences between two-body decays of ?4H and of ??5H are also discussed. (author)

1996-01-01

414

Verbal subgroups of hyperbolic groups have infinite width  

CERN Document Server

Let $G$ be a non-elementary hyperbolic group. Let $w$ be a group word such that the set $w[G]$ of all its values in $G$ does not coincide with $G$ or 1. We show that the width of verbal subgroup $w(G)=$ is infinite. That is, there is no such $l\\in\\mathbb Z$ that any $g\\in w(G)$ can be represented as a product of $\\le l$ values of $w$ and their inverses.

Myasnikov, Alexei

2011-01-01

415

Ultrathin amorphous manganese dioxide nanosheets synthesized with controllable width.  

Science.gov (United States)

We present a one-step synthesis process for ultrathin non-crystalline MnO2 nanosheets. Their thickness is about 2 nm and the width varies from 5 to 20 nm. They induce a higher capacitance than zero-dimensional spheres or one-dimensional rods. When heat treated at elevated temperature MnO2 nanosheets partly grow into crystalline Mn2O3 rods. PMID:23851984

Xu, Chengjun; Shi, Shan; Sun, Yige; Chen, Yanyi; Kang, Feiyu

2013-07-23

416

Technique for estimating relocated gap width for gap conductance calculations  

International Nuclear Information System (INIS)

Thermally induced fuel fragmentation and relocation has been demonstrated to influence the thermal behavior of a fuel rod in two ways. The effective fuel pellet conductivity is decreased and pellet-to-cladding heat transfer is improved. This paper presents a correlation between as-built and relocated gap width which, used with the Ross and Stoute Gap Conductance Correlation and an appropriate fuel thermal expansion model, closely predicts the measured gap conductances

1978-11-17

417

Strong interaction shifts and widths in light kaonic atoms  

CERN Multimedia

Energy shifts and line widths of X-ray transitions in kaonic atoms have been measured with an accuracy of about 10%. These data have been interpreted in terms of an optical potential. Whereas earlier approaches based on the free K-N scattering lengths fail to reproduce the data, a set of effective parameters consistent with all now available experiments could be derived. (20 refs).

Backenstoss, Gerhard; Bergström, I; Bounin, P; Bunaciu, T; Egger, J; Hultberg, S; Koch, H; Krell, M; Lynen, U; Ritter, H G; Schwitter, A; Stearns, R

1972-01-01

418

How to Measure the Spreading Width of Superdeformed Nuclei  

International Nuclear Information System (INIS)

A new expression for the branching ratio for the decay via the E1 process in the normal-deformed band of superdeformed nuclei is given within a simple two-level model. Using this expression, the spreading or tunneling width ?? for superdeformed decay can be expressed entirely in terms of experimentally known quantities. We show how to determine the tunneling matrix element V from the measured value of ?? and a statistical model of the energy levels.

2004-09-13

419

W mass and width measurements at the Tevatron  

International Nuclear Information System (INIS)

I present a measurement of the W boson mass (MW) and width (?W) using 200 and 350 pb-1 of CDF Run II data respectively. The measurements, performed in both the electron and muon decay channels, rely on a fit to the W transverse mass distribution. We measure MW = 80413 ± 48 MeV and ?W = 2032 ± 71 MeV which represent the world's single most precise measurements to date.

2007-01-01

420

HIGHLY STABLE ELECTROLYTIC WATER WITH REDUCED NMR HALF LINE WIDTH  

UK PubMed Central (United Kingdom)

Electrolytic acid or alkaline water having a NMR half line width using 17O of from about 45 to less than 51 Hz, and an oxide reduction potential of from -1000 to +200 mV, or from +600 to +1300 mV, topical compositions that contain such water, uses for such water to hydrate skin, deliver drugs and treat various skin and mucosal conditions, and methods and apparatus for manufacturing the water.

CHEN YONGGE; DE NONI ROBERTO

 
 
 
 
421

HIGHLY STABLE ELECTROLYTIC WATER WITH REDUCED NMR HALF LINE WIDTH.  

UK PubMed Central (United Kingdom)

Electrolytic acid or alkaline water having a NMR half line width using 17O of from about 45 to less than 51 Hz, and an oxide reduction potential of from -1000 to +200 mV, or from +600 to +1300 mV, topical compositions that contain such water, uses for such water to hydrate skin, deliver drugs and treat various skin and mucosal conditions, and methods and apparatus for manufacturing the water.

CHEN YONGGE; NONI ROBERTO DE

422

Porous Alumina Films with Width-Controllable Alumina Stripes.  

Science.gov (United States)

Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface. PMID:21170406

Huang, Kai; Huang, Shi-Ming; Pu, Lin; Shi, Yi; Wu, Zhi-Ming; Ji, Li; Kang, Jun-Yong

2010-08-21

423

The Width of Galton- Watson Trees Conditioned by the Size  

Directory of Open Access Journals (Sweden)

Full Text Available It is proved that the moments of the width of Galton-Watson trees of size n and with offspring variance ? 2 are asymptotically given by (?? n) p m p where m p are the moments of the maximum of the local time of a standard scaled Brownian excursion. This is done by combining a weak limit theorem and a tightness estimate. The method is quite general and we state some further applications.

Michael Drmota; Bernhard Gittenberger

2004-01-01

424

Ultrathin amorphous manganese dioxide nanosheets synthesized with controllable width.  

UK PubMed Central (United Kingdom)

We present a one-step synthesis process for ultrathin non-crystalline MnO2 nanosheets. Their thickness is about 2 nm and the width varies from 5 to 20 nm. They induce a higher capacitance than zero-dimensional spheres or one-dimensional rods. When heat treated at elevated temperature MnO2 nanosheets partly grow into crystalline Mn2O3 rods.

Xu C; Shi S; Sun Y; Chen Y; Kang F

2013-07-01

425

Porous Alumina Films with Width-Controllable Alumina Stripes  

Science.gov (United States)

Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface.

Huang, Kai; Huang, Shi-Ming; Pu, Lin; Shi, Yi; Wu, Zhi-Ming; Ji, Li; Kang, Jun-Yong

2010-12-01

426

Porous Alumina Films with Width-Controllable Alumina Stripes  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface.

Huang Kai; Huang Shi-Ming; Pu Lin; Shi Yi; Wu Zhi-Ming; Ji Li; Kang Jun-Yong

2010-01-01

427

Porous Alumina Films with Width-Controllable Alumina Stripes.  

UK PubMed Central (United Kingdom)

Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface.

Huang K; Huang SM; Pu L; Shi Y; Wu ZM; Ji L; Kang JY

2010-01-01

428

Sonographic measurement of the width of the spinal canal  

International Nuclear Information System (INIS)

Sonographic evaluation of the width of spinal canal information received, concerning accuracy and especially quantity of CT or myelography is inferior compared to. The advantage of sonography is the lacking of X-ray exposure, the non-invasive procedure and the low cost of us apparat and operational time. For these reasons sonography is favoured as a screening method in detecting spinal canal stenosis in a group whose handicap was largely occupational or Sport-related. (orig.).

1985-01-01

429

Sonographic measurement of the width of the spinal canal  

Energy Technology Data Exchange (ETDEWEB)

Sonographic evaluation of the width of spinal canal information received, concerning accuracy and especially quantity of CT or myelography is inferior compared to. The advantage of sonography is the lacking of X-ray exposure, the non-invasive procedure and the low cost of us apparat and operational time. For these reasons sonography is favoured as a screening method in detecting spinal canal stenosis in a group whose handicap was largely occupational or Sport-related.

Helzel, M.V.; Betz, H.; Gladziwa, U.; Frey, M.

1985-06-01

430

Axial couplings and strong decay widths of heavy hadrons.  

UK PubMed Central (United Kingdom)

We calculate the axial couplings of mesons and baryons containing a heavy quark in the static limit using lattice QCD. These couplings determine the leading interactions in heavy hadron chiral perturbation theory and are central quantities in heavy quark physics, as they control strong decay widths and the light quark mass dependence of heavy hadron observables. Our analysis makes use of lattice data at six different pion masses, 227 MeVwidths with experimental data for ?(c)(*) decays, we obtain ?[?(b)(*)??(b)?(±)]=4.2(1.0), 4.8(1.1), 7.3(1.6), 7.8(1.8) MeV for the ?(b)(+), ?(b)(-), ?(b)(*+), ?(b)(*-) initial states, respectively. We also derive upper bounds on the widths of the ?(b)(I(*)) baryons.

Detmold W; Lin CJ; Meinel S

2012-04-01

431

Pulse width control loop as a duty cycle corrector  

Directory of Open Access Journals (Sweden)

Full Text Available The clock distribution and generation circuitry forms a critical component of current synchronous digital systems. A digital system’s clocks must have not only low jitter, low skew, but also well-controlled duty cycle in order to facilitate versatile clocking techniques. In high-speed CMOS clock buffer design, the duty cycle of a clock is liable to be changed when the clock passes through a multistage buffer because the circuit is not pure digital [8]. In this paper, we propose a pulse width control loop referred as MPWCL (modified pulse width control loop) that adopts the same architecture as the conventional PWCL, but with a new pulse generator and new charge pump circuit as a constituent of the duty cycle detector. Thanks to using new building blocks the proposed pulse width control loop can control the duty cycle in a wide range, and what is more important it becomes operative in saturation region too, what provides conditional for fast locking time. For 1.2 µm double-metal double-poly CMOS process with Vdd = 5 V and operating frequency of 133 MHz, results of SPICE simulation show that the duty cycle can be well controlled in the range from 20 % up to 80 % if the loop parameters are properly chosen.

Jovanovi? Goran; Stoj?ev Mile K.

2004-01-01

432

Quantum corral resonance widths: lossy scattering as acoustics.  

UK PubMed Central (United Kingdom)

We present an approach to predicting extrinsic electron resonance widths within quantum corral nanostructures based on analogies with acoustics. Established quantum mechanical methods for calculating resonance widths, such as multiple scattering theory, build up the scattering atom by atom, ignoring the structure formed by the atoms, such as walls or enclosures. Conversely, particle-in-a-box models, assuming continuous walls, have long been successful in predicting quantum corral energy levels, but not resonance widths. In acoustics, partial reflection from walls and various enclosures has long been incorporated for determining reverberation times. Pursuing an exact analogy between the local density of states of a quantum corral and the acoustic impedance of a concert hall, we show electron lifetimes in nanoscopic structures of arbitrary convex shape are well accounted for by the Sabine formula for acoustic reverberation times. This provides a particularly compact and intuitive prescription for extrinsic finite lifetimes in a particle-in-a-box with leaky walls, including quantum corral atomic walls, given single particle scattering properties.

Barr MC; Zaletel MP; Heller EJ

2010-09-01

433

Quantum corral resonance widths: lossy scattering as acoustics.  

Science.gov (United States)

We present an approach to predicting extrinsic electron resonance widths within quantum corral nanostructures based on analogies with acoustics. Established quantum mechanical methods for calculating resonance widths, such as multiple scattering theory, build up the scattering atom by atom, ignoring the structure formed by the atoms, such as walls or enclosures. Conversely, particle-in-a-box models, assuming continuous walls, have long been successful in predicting quantum corral energy levels, but not resonance widths. In acoustics, partial reflection from walls and various enclosures has long been incorporated for determining reverberation times. Pursuing an exact analogy between the local density of states of a quantum corral and the acoustic impedance of a concert hall, we show electron lifetimes in nanoscopic structures of arbitrary convex shape are well accounted for by the Sabine formula for acoustic reverberation times. This provides a particularly compact and intuitive prescription for extrinsic finite lifetimes in a particle-in-a-box with leaky walls, including quantum corral atomic walls, given single particle scattering properties. PMID:20684508

Barr, Matthew C; Zaletel, Michael P; Heller, Eric J

2010-09-01

434

Negative translations not intuitionistically equivalent to the usual ones  

CERN Document Server

We refute the conjecture that all negative translations are intuitionistically equivalent by giving two counterexamples. Then we characterise the negative translations intuitionistically equivalent to the usual ones.

Gaspar, Jaime

2010-01-01

435

Breast composition and radiographic breast equivalence.  

UK PubMed Central (United Kingdom)

The composition of the female breast is an elusive variable in screen-film mammography that has a vital role in determining both the radiographic image quality and breast radiation dose. Despite the large volume of research in mammography only two studies known to the author define the chemical composition of the two major breast constituents, fibrous glandular tissue and adipose tissue. Unfortunately there is not complete agreement between these two studies. Upon this basis, a variety of breast phantom materials have been suggested and developed. This paper examines the radiographic equivalence of some of these materials dealing notably with formulations given by Hammerstein et al and ICRU Report 44, as well as BR12, water, and lucite. Radiographic equivalence was calculated using a computer simulation of mammographic spectra (after the example of Birch and Marshall and Tucker et al, and fitted to available FDA data) applied to attenuation data of phantom materials, in turn based on elemental linear attenuation coefficient data. A software algorithm was written that iteratively calculates the thickness of a nominated material required to match the attenuation of another material of particular thickness. The equivalence of 2-8 cm of lucite to various phantom materials was calculated for molybdenum target, molybdenum filter (Mo/Mo) x-ray beams from 25 to 35 kVp and for Mo/Rh and Rh/Rh beams from 27 to 35 kVp. It was found that for Mo/Mo beams the equivalent thickness of breast phantom material for certain thicknesses of lucite was largely independent of x-ray beam energy with the range of thickness equivalences being less than 3% at 8 cm of lucite and less than 0.5% at 2 cm of lucite. The RMI 156 breast phantom was found to be equivalent to 42 mm of Hammerstein et al. 50% glandular/50% adipose phantom material for Mo/Mo beams at 27 kVp, increasing to 43 mm for the range of Rh/Rh beams. While some questions remain on the accuracy of the present composition of breast constituents, it is clear that various breast compositions can be successfully simulated by using an appropriate thickness of lucite material. The use of lucite breast phantoms is then seen as an effective and reliable way of evaluating mammographic image quality and for calculating breast dose for varying required breast compositions.

McLean D

1997-03-01

436

Breast composition and radiographic breast equivalence  

International Nuclear Information System (INIS)

[en] Full text: The composition of the female breast is an allusive variable in screen-film mammography that has a vital role in determining both the radiographic image quality and breast radiation dose. Despite the large volume of research in mammography only two studies known to the author define the chemical composition of the two major breast constituents, fibrous glandular tissue and adipose tissue. Unfortunately there is not complete agreement between these two studies. Upon this basis a variety of breast phantom materials have been suggested and developed. This paper examines the radiographic equivalence of some of these material dealing notably with the formulations given by Hammerstein GR et al (Radiol, 130:485-491, 1979) and ICRU (Report 44, 1989) as well as BR12 (White DR, et al, Brit. J. Radiol. 50:814821, 1977), water and lucite. Radiographic equivalence was calculated using a computer simulation of mammographic spectra (after the example of Birch and Marshall (Phys Med Biol 24(3):505-517, 1979) and Tucker et al (Med. Phys. 18(3):402-407, 1991) and fitted to available FDA data) applied to attenuation data of phantom materials in turn based on elemental linear attenuation coefficient data. A software algorithm was written that iteratively calculates the thickness of a nominated material required to match the attenuation of another material of particular thickness. The equivalence of 2 - 8 cm of lucite to various phantom materials was calculated for molybdenum target, molybdenum filter (Mo/Mo) x-ray beams from 25 to 35 kVp and for Mo/Rh and Rh/Rh beams from 27 to 35 kVp. It was found that for Mo/Mo beams the equivalent thickness of breast phantom material for certain thicknesses of lucite was largely independent of x-ray beam energy with the range of thickness equivalences being less than 3% at 8 cm of lucite and less than 0.5% at 2 cm of lucite. The RMI 156 breast phantom was found to be equivalent to 42 cm of Hammerstein 50% glandular/ 50% adipose phantom material for Mo/Mo beams at 27 kVp, increasing to 43 cm for the range of Rh/Rh beams. While some question does remain on the accuracy of the present composition of breast constituents it is clear that various breast compositions can be successfully simulated by using an appropriate thickness of lucite material. The use of lucite breast phantoms is then seen as an effective and reliable way of evaluating mammographic image quality and for calculating breast dose for varying required breast compositions

1996-01-01

437

Measurements of the Mass, Total Width and Two-Photon Partial Width of the $\\eta_{c}$ Meson  

CERN Multimedia

Using 13.4 $fb^{-1}$ of data collected with the CLEO detector at the Cornell Electron Storage Ring, we have observed 300 events for the two-photon production of ground-state pseudo-scalar charmonium in the decay $\\eta_c$ -> $K_S K^{\\mp} \\pi^{\\pm}$. We have measured the $\\eta_c$ mass to be (2980.4 +- 2.3 (stat) +- 0.6 (sys)) MeV and its full width as (27.0 +- 5.8 (stat) +- 1.4 (sys)) MeV. We have determined the two-photon partial width of the $\\eta_c$ meson to be (7.6 +- 0.8 (stat) +- 0.4 (sys) +- 2.3 (br)) keV, with the last uncertainty associated with the decay branching fraction.

Brandenburg, G; Gao, Y S; Kim, D Y J; Wilson, R; Browder, T E; Li, Y; Rodríguez, J L; Yamamoto, H; Bergfeld, T; Eisenstein, B I; Ernst, J; Gladding, G E; Gollin, G D; Hans, R M; Johnson, E; Karliner, I; Marsh, M A; Palmer, M; Plager, C; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Janicek, R; Patel, P M; Sadoff, A J; Ammar, R; Bean, A; Besson, D; Davis, R; Kwak, N; Zhao, X; Anderson, S; Frolov, V V; Kubota, Y; Lee, S J; Mahapatra, R; O'Neill, J J; Poling, R A; Riehle, T; Smith, A; Stepaniak, C J; Urheim, J; Ahmed, S; Alam, M S; Athar, S B; Jian, L; Ling, L; Saleem, M; Timm, S; Wappler, F; Anastassov, A; Duboscq, J E; Eckhart, E; Gan, K K; Gwon, C; Hart, T; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pedlar, T K; Schwarthoff, H; Thayer, J B; Von Törne, E; Zoeller, M M; Richichi, S J; Severini, H; Skubic, P L; Undrus, A; Chen, S; Fast, J; Hinson, J W; Lee, J; Miller, D H; Shibata, E I; Shipsey, I P J; Pavlunin, V; Cronin-Hennessy, D; Lyon, A L; Thorndike, E H; Jessop, C P; Marsiske, H; Perl, Martin Lewis; Savinov, V; Ugolini, D W; Zhou, X; Coan, T E; Fadeev, V; Maravin, Y; Narsky, I; Stroynowski, R; Ye, J; Wlodek, T; Artuso, M; Ayad, R; Boulahouache, C; Bukin, K; Dambasuren, E; Karamov, S; Majumder, G; Moneti, G C; Mountain, R; Schuh, S; Skwarnicki, T; Stone, S; Viehhauser, G; Wang, J C; Wolf, A; Wu, J; Kopp, S E; Mahmood, A H; Csorna, S E; Danko, I; McLean, K W; Marka, S; Xu, Z; Godang, R; Kinoshita, K; Lai, I C; Schrenk, S; Bonvicini, G; Cinabro, D; McGee, S; Perera, L P; Zhou, G J; Lipeles, E; Pappas, S P; Schmidtler, M; Shapiro, A; Sun, W M; Weinstein, A J; Würthwein, F; Jaffe, D E; Masek, G E; Paar, H P; Potter, E M; Prell, S; Sharma, V; Asner, D M; Eppich, A; Hill, T S; Morrison, R J; Briere, R A; Ferguson, T; Vogel, H; Behrens, B H; Ford, W T; Gritsan, A; Roy, J D; Smith, J G; Alexander, J P; Baker, R; Bebek, C; Berger, B E; Berkelman, K; Blanc, F; Boisvert, V; Cassel, David G; Dickson, M; Drell, P S; Ecklund, K M; Ehrlich, R; Foland, A D; Gaidarev, P B; Galik, R S; Gibbons, L K; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hopman, P I; Jones, C D; Kreinick, D L; Lohner, M; Magerkurth, A; Meyer, T O; Mistry, N B; Nordberg, E; Patterson, J R; Peterson, D; Riley, D; Thayer, J G; Thies, P G; Urner, D; Valant-Spaight, B L; Warburton, A; Avery, P; Prescott, C; Rubiera, A I; Yelton, J; Zheng, J

2000-01-01

438

Measurements of the mass, total width, and two-photon partial width of the eta(c) meson.  

UK PubMed Central (United Kingdom)

Using 13.4 fb(-1) of data collected with the CLEO detector at the Cornell Electron Storage Ring, we have observed 300 events for the two-photon production of ground-state pseudoscalar charmonium in the decay eta(c)-->K(0)(S)K-/+pi(+/-). We have measured the eta(c) mass to be [2980.4+/-2.3 (stat)+/-0.6 (syst)] MeV and its full width as [27.0+/-5.8 (stat)+/-1.4 (syst)] MeV. We have determined the two-photon partial width of the eta(c) meson to be [7.6+/-0.8 (stat)+/-0.4 (syst)+/-2.3 (br)] keV, with the last uncertainty associated with the decay branching fraction.

Brandenburg G; Ershov A; Gao YS; Kim DY; Wilson R; Browder TE; Li Y; Rodriguez JL; Yamamoto H; Bergfeld T; Eisenstein BI; Ernst J; Gladding GE; Gollin GD; Hans RM; Johnson E; Karliner I; Marsh MA; Palmer M; Plager C; Sedlack C; Selen M; Thaler JJ; Williams J; Edwards KW; Janicek R; Patel PM; Sadoff AJ; Ammar R; Bean A; Besson D; Davis R; Kwak N; Zhao X; Anderson S; Frolov VV; Kubota Y; Lee SJ; Mahapatra R; O'Neill JJ; Poling R; Riehle T; Smith A; Stepaniak CJ; Urheim J; Ahmed S; Alam MS; Athar SB; Jian L; Ling L; Saleem M; Timm S; Wappler F; Anastassov A; Duboscq JE; Eckhart E; Gan KK; Gwon C; Hart T; Honscheid K; Hufnagel D; Kagan H; Kass R; Pedlar TK; Schwarthoff H; Thayer JB; von Toerne E; Zoeller MM; Richichi SJ; Severini H; Skubic P; Undrus A; Chen S; Fast J; Hinson JW; Lee J; Miller DH; Shibata EI; Shipsey IP; Pavlunin V; Cronin-Hennessy D; Lyon AL; Thorndike EH; Jessop CP; Marsiske H; Perl ML; Savinov V; Ugolini D; Zhou X; Coan TE; Fadeyev V; Maravin Y; Narsky I; Stroynowski R; Ye J; Wlodek T; Artuso M; Ayad R; Boulahouache C; Bukin K; Dambasuren E; Karamov S; Majumder G; Moneti GC; Mountain R; Schuh S; Skwarnicki T; Stone S; Viehhauser G; Wang JC; Wolf A; Wu J; Kopp S; Mahmood AH; Csorna SE; Danko I; McLean KW; Márka S; Xu Z; Godang R; Kinoshita K; Lai IC; Schrenk S; Bonvicini G; Cinabro D; McGee S; Perera LP; Zhou GJ; Lipeles E; Pappas SP; Schmidtler M; Shapiro A; Sun WM; Weinstein AJ; Würthwein F; Jaffe DE; Masek G; Paar HP; Potter EM; Prell S; Sharma V; Asner DM; Eppich A; Hill TS; Morrison RJ; Briere RA; Ferguson T; Vogel H; Behrens BH; Ford WT; Gritsan A; Roy J; Smith JG; Alexander JP; Baker R; Bebek C; Berger BE; Berkelman K; Blanc F; Boisvert V; Cassel DG; Dickson M; Drell PS; Ecklund KM; Ehrlich R; Foland AD; Gaidarev P; Galik RS; Gibbons L; Gittelman B; Gray SW; Hartill DL; Heltsley BK; Hopman PI; Jones CD; Kreinick DL; Lohner M; Magerkurth A; Meyer TO; Mistry NB; Nordberg E; Patterson JR; Peterson D; Riley D; Thayer JG; Thies PG; Urner D; Valant-Spaight B; Warburton A; Avery P; Prescott C; Rubiera AI; Yelton J; Zheng J

2000-10-01

439

Equivalence Theory Applied to Anisotropic Thin Plates  

Directory of Open Access Journals (Sweden)

Full Text Available We extend the Equivalence Theory (ET) formulated by Absi [1] for the statics of isotropic materials to the statics and dynamics of orthotropic materials. That theory relies on the assumption that any real body mod- eling may be substituted by another one that, even though it may possibly have material constitutive laws and geometric properties with no physical sense (like negative cross sections or Young modulus), is intended to be more advantageous for calculus. In our approach, the equivalence is expressed by equating both the effective strain energies of the two models and the material structural weights in dynamics [2]. We provide a numerical analysis of the convergence properties of ET approach while comparing its numerical results with those predicted by the analytical theory and the Finite Elements Method for thin plates.

Madjid Haddad; Yves Gourinat; Miguel Charlotte

2011-01-01

440

Strong Equivalence of Qualitative Optimization Problems  

CERN Multimedia

We introduce the framework of qualitative optimization problems (or, simply, optimization problems) to represent preference theories. The formalism uses separate modules to describe the space of outcomes to be compared (the generator) and the preferences on outcomes (the selector). We consider two types of optimization problems. They differ in the way the generator, which we model by a propositional theory, is interpreted: by the standard propositional logic semantics, and by the equilibrium-model (answer-set) semantics. Under the latter interpretation of generators, optimization problems directly generalize answer-set optimization programs proposed previously. We study strong equivalence of optimization problems, which guarantees their interchangeability within any larger context. We characterize several versions of strong equivalence obtained by restricting the class of optimization problems that can be used as extensions and establish the complexity of associated reasoning tasks. Understanding strong equiv...

Faber, Wolfgang; Woltran, Stefan

2011-01-01