Navegação Ciências Exatas e da Terra por Título

Resultados 5920-5939 de 5955

    • Whole Earth Telescope observations of the hot helium atmosphere pulsating white dwarf EC 20058−5234 

      Sullivan, Denis J.; Metcalfe, Travis S.; O'Donoghue, Darragh; Winget, Donald Earl; Kilkenny, Dave; Van Wyk, Francois; Kanaan Neto, Antonio Nemer; Kepler, Souza Oliveira; Nitta, Atsuko; Kawaler, Steven D.; Montgomery, Michael Houston; Nather, R. Edward; O'Brien, M. Sean; Bischoff-Kim, Agnès; Wood, Matthew A.; Jiang, Xiaojun; Leibowitz, Elia M.; Ibbetson, Peter A.; Zola, Staszek; Krzesinski, Jerzy; Pajdosz, Gabriel; Vauclair, Gérard; Dolez, Noël; Chevreton, Michel (2008) [Artigo de periódico]
      We present the analysis of a total of 177 h of high-quality optical time-series photometry of the helium atmosphere pulsating white dwarf (DBV) EC 20058−5234. The bulk of the observations (135 h) were obtained during a WET ...

    • Whole earth telescope observations of the interacting binary white dwarf v803 cen in its low state 

      O'Donoghue, Darragh; Wargau, W.; Warner, B.; Kilkenny, Dave; Martinez, Peter; Kanaan Neto, Antonio Nemer; Kepler, Souza Oliveira; Henry, G.W.; Winget, Donald Earl; Clemens, J. Christopher; Grauer, Albert D. (1990) [Artigo de periódico]
      Using a network of observatories in the southern hemisphere, high-speed photometry of the interacting binary white dwarf (IBWD) V803 Cen in its low state is presented. Because of the faintness of the system, the 1611-s ...

    • Whole earth telescope observations of the pulsating hot white dwarf PG 1707+427 

      Kawaler, Steven D.; Potter, E. M.; Vuckovic, Maja; O'Toole, Simon; Clemens, J. Christopher; O'Brien, M. Sean; Grauer, Albert D.; Nather, R. Edward; Moskalik, Pawel; Fontaine, Gilles; Wesemael, F.; Bergeron, Pierre; Vauclair, Gérard; Dolez, Noël; Chevreton, Michel; Kleinman, Scot James; Watson, Todd K.; Barstow, Martin A.; Dind, Z. E.; Sansom, A.E.; Winget, Donald Earl; Kepler, Souza Oliveira; Kanaan Neto, Antonio Nemer; Bradley, Paul A.; Dixson, James S.; Provencal, Judith L.; Bedding, T. R. (2004) [Artigo de periódico]
      We report on the analysis of multisite time-series photometry of the pulsating pre-white dwarf (GW Vir star) PG 1707+427, obtained by the Whole Earth Telescope collaboration. This is the last of the known GW Vir stars ...

    • Whole Earth Telescope observations of the pulsating subdwarf B star PG 0014+067 

      Vuckovic, Maja; Kawaler, Steven D.; O'Toole, Simon; Csubry, Z.; Baran, Andrzej; Zola, Staszek; Moskalik, Pawel; Klumpe, Eric W.; Riddle, Reed L.; O'Brien, M. Sean; Mullally, Fergal; Wood, Matthew A.; Wilkat, Vanessa; Zhou, Ai-Ying; Reed, M. D.; Terndrup, Donald M.; Sullivan, Denis J.; Kim, Seung-Lee; Chen, Wen-Ping; Chen, C.-W.; Hsiao, Wen-Shan; Kausharbanu, Sanchawala; Lee, Hsu-Tai; Jiang, Xiaojun; Janulis, Rimvydas; Siwak, Michal; Ogloza, Waldemar; Paparo, Margit; Bognár, Zsófia; Sódor, Ádám; Handler, Gerald; Lorenz, Denise; Steininger, Bruno; Silvotti, Roberto; Vauclair, Gérard; Oreiro, Raquel; Ostensen, Roy; Bronowska, A.; Castanheira, Bárbara Garcia; Kepler, Souza Oliveira; Fraga, Luciano; Shipman, Harry L.; Provencal, Judith L.; Childers, D. (2006) [Artigo de periódico]
      PG 0014+067 is one of the most promising pulsating subdwarf B stars for seismic analysis, as it has a rich pulsation spectrum. The richness of its pulsations, however, poses a fundamental challenge to understanding the ...

    • Whole Earth Telescope observations of the subdwarf B star KPD1930+2752 : a rich, short-period pulsator in a close binary 

      Reed, M. D.; Harms, S. L.; Poindexter, S.; Zhou, Ai-Ying; Eggen, J.; Morris, M. A.; Quint, A. C.; McDaniel, S.; Baran, Andrzej; Dolez, Noël; Kawaler, Steven D.; Kurtz, Donald W.; Moskalik, Pawel; Riddle, Reed L.; Zola, Staszek; Ostensen, Roy; Solheim, Jan-Eric; Kepler, Souza Oliveira; Costa, Alex Fabiano Murillo da; Provencal, Judith L.; Mullally, Fergal; Winget, Donald Earl; Vuckovic, Maja; Crowe, Richard A.; Terry, D.; Avila, R.; Berkey, B.; Stewart, S.; Bodnarik, J.; Bolton, D.; Binder, Philippe M.; Sekiguchi, Kazuhiro; Sullivan, Denis J.; Kim, Seung-Lee; Chen, Wen-Ping; Chen, C.-W.; Lin, Hung-Chin; Jiang, Xiaojun; Wu, H.; Gou, J.-P.; Liu, Z.; Leibowitz, Elia M.; Lipkin, Y.; Akan, Mustafa Can; Cakirli, Ö; Janulis, Rimvydas; Pretorius, R.; Ogloza, Waldemar; Stachowski, G.; Paparo, Margit; Szabó, R.; Csubry, Z.; Zsuffa, D.; Silvotti, Roberto; Marinoni, S.; Bruni, I.; Vauclair, Gérard; Chevreton, Michel; Matthews, Jaymie M.; Cameron, C.; Pablo, H. (2011) [Artigo de periódico]
      KPD 1930+2752 is a short-period pulsating subdwarf B (sdB) star. It is also an ellipsoidal variable with a known binary period of 2.3 h. The companion is most likely a white dwarf and the total mass of the system is close ...

    • Whole Earth Telescope observations of the white dwarf G29-38 : phase variations of the 615 second period 

      Winget, Donald Earl; Nather, R. Edward; Clemens, J. Christopher; Provencal, Judith L.; Kleinman, Scot James; Bradley, Paul A.; Wood, Matthew A.; Claver, C.F.; Robinson, E.L.; Grauer, Albert D.; Hine, B.P.; Fontaine, Gilles; Achilleos, Nicholas; Marar, T.M. Krishnan; Seetha, S.; Ashoka, B.N.; O'Donoghue, Darragh; Warner, B.; Kurtz, Donald W.; Martinez, Peter; Vauclair, Gérard; Chevreton, Michel; Augusteijn, T.; Paradijs, J. van; Hansen, Carl J.; Liebert, James; Kanaan Neto, Antonio Nemer; Kepler, Souza Oliveira (1990) [Artigo de periódico]
      Using an extensive set of high-speed photometric observations obtained with the Whole Earth Telescope network, we show that the complex light curve of the ZZ Ceti (DAV) star G29-38 is dominated by a single, constant amplitude ...

    • Whole Earth Telescope observations of V471 Tauri : the nature of the white dwarf variations 

      Clemens, J. Christopher; Nather, R. Edward; Winget, Donald Earl; Robinson, E.L.; Wood, Matthew A.; Claver, C.F.; Provencal, Judith L.; Kleinman, Scot James; Bradley, Paul A.; Frueh, M.L.; Grauer, Albert D.; Hine, B.P.; Fontaine, Gilles; Achilleos, Nicholas; Wickramasinghe, D.T.; Marar, T.M. Krishnan; Seetha, S.; Ashoka, B.N.; O'Donoghue, Darragh; Warner, B.; Kurtz, Donald W.; Martinez, Peter; Vauclair, Gérard; Chevreton, Michel; Barstow, Martin A.; Kanaan Neto, Antonio Nemer; Kepler, Souza Oliveira; Augusteijn, T.; Paradijs, J. van; Hansen, Carl J. (1992) [Artigo de periódico]
      We have conducted time-series photometric observations of the binary star V471 Tauri using the Whole Earth Telescope observing network. Our purpose was to determine the mechanism responsible for causing the 555 and 277 s ...

    • Widespread star formation inside galactic outflows 

      Gallagher, Robert; Maiolino, Roberto; Belfiore, Francesco; Drory, Niv; Riffel, Rogério; Riffel, Rogemar André (2019) [Artigo de periódico]
      Several models have predicted that stars could form inside galactic outflows and that this would be a new major mode of galaxy evolution. Observations of galactic outflows have revealed that they host large amounts of dense ...

    • Widom insertion method in simulations with Ewald summation 

      Bakhshandeh, Amin; Levin, Yan (2022) [Artigo de periódico]
      We discuss the application of the Widom insertion method for calculation of the chemical potential of individual ions in computer simulations with Ewald summation. Two approaches are considered. In the first approach, an ...

    • Wilson Ratio of Fermi Gases in One Dimension 

      Guan, Xi-Wen; Yin, Xiangguo; Foerster, Angela; Batchelor, Murray T.; Lee, Chaohong; Lin, Hai-Qing (2013) [Artigo de periódico]
      We calculate the Wilson ratio of the one-dimensional Fermi gas with spin imbalance. The Wilson ratio of attractively interacting fermions is solely determined by the density stiffness and sound velocity of pairs and of ...

    • Word and face recognition processing based on response times and ex-Gaussian components 

      Moret-Tatay, Carmen; Gallego, David García-Ramos; Sáiz-Mauleón, Begoña; Gamermann, Daniel; Bertheaux, Cyril; Borg, Céline (2021) [Artigo de periódico]
      The face is a fundamental feature of our identity. In humans, the existence of specialized processing modules for faces is now widely accepted. However, identifying the processes involved for proper names is more problematic. ...

    • Workflow modelling using a temporal object-oriented model with roles 

      Edelweiss, Nina; Nicolao, Mariano (2004) [Artigo de periódico]
      The representation of all the processes that compose a workflow, including all the constituent activities, their execution sequence and relationships, the agents responsible for their execution, and the resources that are ...

    • Wrappers feature selection in alzheimer’s biomarkers using kNN and SMOTE oversampling 

      Rodrigues, Yuri Elias; Manica, Evandro; Zimmer, Eduardo Rigon; Pascoal, Tharick Ali; Mathotaarachchi, Sulantha Sanjeewa; Rosa Neto, Pedro (2017) [Artigo de periódico]
      Biomarkers are characteristics that are objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes or pharmacological responses to a therapeutic intervention. The combination ...

    • W+ W− boson pair production in proton-proton collisions at √s=13  TeV 

      Sirunyan, A. M.; Silveira, Gustavo Gil da; CMS Collaboration (2020) [Artigo de periódico]
      A measurement of the W+W− boson pair production cross section in proton-proton collisions at s=13  TeV is presented. The data used in this study are collected with the CMS detector at the CERN LHC and correspond to an ...

    • Xerogel p-anisidinapropilsílica : estudo da estabilidade térmica e da resistência à lixiviação com solventes 

      Franken, Leonardo; Santos, Lisiane Santos dos; Caramão, Elina Bastos; Costa, Tania Maria Haas; Benvenutti, Edilson Valmir (2002) [Artigo de periódico]
      The xerogel p-anisidinepropylsilica was obtained. This solid presents some residual paraffin and also a small fraction of high organofunctionalized material that was leached in polar solvent. The xerogel purification could ...

    • X-ray-absorption spectroscopy and x-ray diffraction in discontinuous Co/sub x/Fe/sub 1-x//Ag multilayers 

      Flores, Wladimir Hernandez; Teixeira, Sergio Ribeiro; Cunha, Joao Batista Marimon da; Alves, Maria do Carmo Martins; Tolentino, Hélio Cesar Nogueira; Traverse, Agnes (2000) [Artigo de periódico]
      This paper reports on the structural properties of CoxFe12x /Ag discontinuous multilayers with x 50, 0.3, 0.7, and 1. The evolution of the structural properties has been investigated by x-ray diffraction and x-ray-absorption ...

    • Young star clusters immersed in intermediate-age fields in the Large Magellanic Cloud bar 

      Piatti, Andres E.; Geisler, Doug; Bica, Eduardo Luiz Damiani; Claria Olmedo, Juan Jose (2003) [Artigo de periódico]
      We present Washington System photometry for 11 star clusters immersed in the north-west part of the Large Magellanic Cloud (LMC) bar, centred on the intermediate-age clusters NGC 1865 and SL 244. The fields are heavily ...

    • Young star clusters in the Large Magellanic Cloud : NGC 1805 and 1818 

      Johnson, Rachel A.; Beaulieu, Sylvie F.; Gilmore, Gerard Fitzgerald; Hurley, Jarrod; Santiago, Basilio Xavier; Tanvir, Nial R.; Elson, Rebecca A.W. (2001) [Artigo de periódico]
      We present colour-magnitude diagrams for two rich (~~104 M̛) Large Magellanic Cloud star clusters with ages ~~ 107 yr, constructed from optical and near-infrared data obtained with the Hubble Space Telescope. These data ...

    • Young (α/Fe)-enhanced stars discovered by CoRoT and APOGEE : what is their origin? 

      Chiappini, C.C.M.; Anders, Friedrich; Rodrigues, Thaise da Silva; Miglio, Andrea; Montalbán, Josefina; Mosser, Benoît; Girardi, Leo Alberto; Valentini, Marica; Noels, Arlette; Morel , Thierry; Minchev, Ivan; Steinmetz, M.; Santiago, Basilio Xavier; Schultheis, Mathias; Martig, Marie; Costa, Luiz N. da; Maia, Marcio Antonio Geimba; Allende Prieto, Carlos; Assis Peralta, R. de; Hekker, Saskia; Themeßl, Nathalie; Kallinger, Thomas; Garcia, Rafael A.; Mathur, Savita; Baudin, Frederic; Beers, T.C.; Cunha, Katia; Harding, Paul; Holtzman, J.A.; Majewski, Steven Raymond; Mészáros, S.; Nidever, D.L.; Pan, K.; Schiavon, Ricardo P.; Shetrone, M.; Schneider, D.P.; Stassun, Keivan G. (2015) [Artigo de periódico]
      We report the discovery of a group of apparently young CoRoT red-giant stars exhibiting enhanced [ /Fe] abundance ratios (as determined from APOGEE spectra) with respect to solar values. Their existence is not explained ...

    • Yukawa particles in a confining potential 

      Girotto, Matheus; Santos, Alexandre Pereira dos; Colla, Thiago Escobar; Levin, Yan (2014) [Artigo de periódico]
      We study the density distribution of repulsive Yukawa particles confined by an external potential. In the weak coupling limit, we show that the mean-field theory is able to accurately account for the particle distribution. ...