Search Results - "Castanheira, B."

Effects of Magnetic Fields in Hot White Dwarfs by Peterson, J., Dexheimer, V., Negreiros, R., Castanheira, B. G.

“…Abstract In this work, we study the effects of magnetic fields on hot white dwarfs. We model their interior as a nuclei lattice surrounded by a relativistic…”
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Toward ensemble asteroseismology of ZZCeti stars with fully evolutionary models by Romero, A. D, Córsico, A. H, Althaus, L. G, Kepler, S. O, Castanheira, B. G, Miller Bertolami, M. M

“…ABSTRACT ZZCeti stars form the most numerous group of degenerate variable stars. They are otherwise normal DA (H-rich atmospheres) white dwarfs that exhibit…”
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The sdA problem – II. Photometric and spectroscopic follow-up by Pelisoli, Ingrid, Kepler, S O, Koester, D, Castanheira, B G, Romero, A D, Fraga, L

“…ABSTRACT The spectral classification ‘subdwarf A’ (sdA) is given to stars showing H-rich spectra and sub-main-sequence surface gravities, but effective…”
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Magnetic white dwarf stars in the Sloan Digital Sky Survey by Kepler, S. O., Pelisoli, I., Jordan, S., Kleinman, S. J., Koester, D., Külebi, B., Peçanha, V., Castanheira, B. G., Nitta, A., Costa, J. E. S., Winget, D. E., Kanaan, A., Fraga, L.

“…To obtain better statistics on the occurrence of magnetism among white dwarfs, we searched the spectra of the hydrogen atmosphere white dwarf stars (DAs) in…”
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Seismological studies of ZZ Ceti stars – II. Application to the ZZ Ceti class by Castanheira, B. G., Kepler, S. O.

“…We used the detected pulsation modes and adiabatic pulsation models to do seismology of the class of ZZ Ceti stars and measure the H layer mass for 83 stars…”
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White dwarf mass distribution in the SDSS by Kepler, S. O., Kleinman, S. J., Nitta, A., Koester, D., Castanheira, B. G., Giovannini, O., Costa, A. F. M., Althaus, L.

“…We determined masses for the 7167 DA and 507 DB white dwarf stars classified as single and non-magnetic in Data Release 4 of the Sloan Digital Sky Survey…”
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Pruning The ELM Survey: Characterizing Candidate Low-mass White Dwarfs through Photometric Variability by Bell, Keaton J., Gianninas, A., Hermes, J. J., Winget, D. E., Kilic, Mukremin, Montgomery, M. H., Castanheira, B. G., Vanderbosch, Z., Winget, K. I., Brown, Warren R.

“…We assess the photometric variability of nine stars with spectroscopic Teff and log g values from the ELM Survey that locates them near the empirical extremely…”
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Seismological studies of ZZ Ceti stars - I. The model grid and the application to individual stars by Castanheira, B. G., Kepler, S. O.

“…We calculate and explore an extensive adiabatic model grid for pulsating white dwarfs with hydrogen-dominated atmospheres, the ZZ Ceti stars. We also compared…”
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Discovery of five new massive pulsating white dwarf stars by Castanheira, B. G., Kepler, S. O., Kleinman, S. J., Nitta, A., Fraga, L.

“…Using the SOuthern Astrophysical Research telescope (SOAR) Optical Imager at the SOAR 4.1 m telescope, we report on the discovery of five new massive pulsating…”
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Probing the Structure of Kepler ZZ Ceti Stars with Full Evolutionary Models-based Asteroseismology by Romero, Alejandra D., Córsico, A. H., Castanheira, B. G., Gerónimo, F. C. De, Kepler, S. O., Koester, D., Kawka, A., Althaus, L. G., Hermes, J. J., Bonato, C., Gianninas, A.

“…We present an asteroseismological analysis of four ZZ Ceti stars observed with the Kepler spacecraft: GD 1212, SDSS J113655.17+040952.6, KIC 11911480, and KIC…”
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New developments of the ZZ Ceti instability strip: the discovery of 11 new variables by Castanheira, B. G., Kepler, S. O., Kleinman, S. J., Nitta, A., Fraga, L.

“…Using the The SOuthern Astrophysical Research (SOAR) 4.1-m telescope, we report on the discovery of low amplitude pulsations for three stars previously…”
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Measuring the Evolution of the Most Stable Optical Clock G 117-B15A by Kepler, S. O, Costa, J. E. S, Castanheira, B. G, Winget, D. E, Mullally, Fergal, Nather, R. E, Kilic, Mukremin, von Hippel, Ted, Mukadam, Anjum S, Sullivan, Denis J

“…We report our measurement of the rate of change of period with time (P) for the 215 s periodicity in the pulsating white dwarf G 117-B15 A, the most stable…”
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Biogenic methane and carbon dioxide generation in organic-rich shales from southeastern Brazil by Bertassoli, D.J., Sawakuchi, H.O., Almeida, N.S., Castanheira, B., Alem, V.A.T., Camargo, M.G.P., Krusche, A.V., Brochsztain, S., Sawakuchi, A.O.

“…Brazilian shale formations are potential biogenic gas systems that are still poorly understood. Organic-rich shales from Ponta Grossa (Devonian, Paraná Basin),…”
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Eleven New DA White Dwarf Variable Stars from the Sloan Digital Sky Survey by Mullally, F, Thompson, S. E, Castanheira, B. G, Winget, D. E, Kepler, S. O, Eisenstein, D. J, Kleinman, S. J, Nitta, Atsuko

“…We report the discovery of 11 new variable DA white dwarf (ZZ Ceti) stars. Candidates were selected by deriving temperatures from model fits to spectra…”
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Gemini spectra of 12 000 K white dwarf stars by Kepler, S. O., Castanheira, B. G., Costa, A. F. M., Koester, D.

“…We report signal-to-noise ratio (S/N) ≃ 100 optical spectra for four DA white dwarf stars acquired with the GMOS spectrograph of the 8-m Gemini north…”
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Extensive study of HD 25558, a long-period double-lined binary with two SPB components by Sódor, Á., De Cat, P., Wright, D. J., Neiner, C., Briquet, M., Lampens, P., Dukes, R. J., Henry, G. W., Williamson, M. H., Brunsden, E., Pollard, K. R., Cottrell, P. L., Maisonneuve, F., Kilmartin, P. M., Matthews, J., Kallinger, T., Beck, P. G., Kambe, E., Engelbrecht, C. A., Czanik, R. J., Yang, S., Hashimoto, O., Honda, S., Fu, J. N., Castanheira, B., Lehmann, H., Bognár, Zs, Behara, N., Scaringi, S., Van Winckel, H., Menu, J., Lobel, A., Mathias, P., Saesen, S., Vu kovi, M.

“…We carried out an extensive observational study of the Slowly Pulsating B (SPB) star, HD 25558. The 2000 spectra obtained at different observatories, the…”
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The pulsations of PG 1351+489 by Redaelli, M., Kepler, S. O., Costa, J. E. S., Winget, D. E., Handler, G., Castanheira, B. G., Kanaan, A., Fraga, L., Henrique, P., Giovannini, O., Provencal, J. L., Shipman, H. L., Dalessio, J., Thompson, S. E., Mullally, F., Brewer, M. M., Childers, D., Oksala, M. E., Rosen, R., Wood, M. A., Reed, M. D., Walter, B., Strickland, W., Chandler, D., Watson, T. K., Nather, R. E., Montgomery, M. H., Bischoff-Kim, A., Hansen, C. J., Nitta, A., Kleinman, S. J., Claver, C. F., Brown, T. M., Sullivan, D. J., Kim, S.-L., Chen, W.-P., Yang, M., Shih, C.-Y., Zhang, X., Jiang, X., Fu, J. N., Seetha, S., Ashoka, B. N., Marar, T. M. K., Baliyan, K. S., Vats, H. O., Chernyshev, A. V., Ibbetson, P., Leibowitz, E., Hemar, S., Sergeev, A. V., Andreev, M. V., Janulis, R., Meištas, E. G., Moskalik, P., Pajdosz, G., Baran, A., Winiarski, M., Zola, S., Ogloza, W., Siwak, M., Bognár, Zs, Solheim, J.-E., Sefako, R., Buckley, D., O'Donoghue, D., Nagel, T., Silvotti, R., Bruni, I., Fremy, J. R., Vauclair, G., Chevreton, M., Dolez, N., Pfeiffer, B., Barstow, M. A., Creevey, O. L., Kawaler, S. D., Clemens, J. C.

“…PG 1351+489 is one of the 20 DBVs - pulsating helium-atmosphere white dwarf stars - known and has the simplest power spectrum for this class of star, making it…”
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KIC 4552982: outbursts and pulsations in the longest-ever pseudo-continuous light curve of a ZZ Ceti by Bell, K J, Hermes, J J, Bischoff-Kim, A, Moorhead, S, Castanheira, B G, Montgomery, M H, Winget, D E

“…KIC 4552982 was the first ZZ Ceti (hydrogen-atmosphere pulsating white dwarf) identified to lie in the Kepler field, resulting in the longest pseudo-continuous…”
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Antimicrobial efficacy of alcohol-based hand gels by Guilhermetti, M, Marques Wiirzler, L.A, Castanheira Facio, B, da Silva Furlan, M, Campo Meschial, W, Bronharo Tognim, M.C, Botelho Garcia, L, Luiz Cardoso, C

“…Summary In recent years, several commercial alcohol-based hand gels have appeared on the market to improve the hand-cleansing compliance of healthcare workers…”
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Effects of Magnetic Fields in Hot White Dwarfs by Peterson, J, Dexheimer, V, Negreiros, R, Castanheira, B. G

“…In this work, we study the effects of temperature on magnetic white dwarfs. We model their interior as a nuclei lattice surrounded by a relativistic free Fermi…”
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