Binary Stars
Mostrando 1-8 de 8 artigos, teses e dissertações.
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1. Different approaches to the Composition of Neutron Stars and their Environment / Diferentes abordagens à composição e ao ambiente das estrelas de nêutrons
Even after 80 years of intense research, the composition of neutron stars remains unknown, since both the dense matter in the interior of these compact objects and the matter moving around them are in extreme physical conditions, unreproducible in terrestrial laboratories. In this Thesis, we follow four different interconnected ways to approach these extreme
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 12/04/2012
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2. Sistemas binários eclipsantes na missão CoRot
Sessenta e cinco sistemas binários eclipsantes, identificados nos objetivos da missão espacial CoRoT, foram selecionados para a análise. Destes, cinquenta e nove curvas de luz fotométricas que foram analisadas e processadas neste estudo são curvas cromáticas (simultaneamente observadas nos trêsfiltros azul, verde e vermelho do satélite), fornecendo u
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 18/08/2011
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3. Candidatos a variáveis cataclísmicas magnéticas com polarização baixa / Candidates for magnetic the cataclysmic variables having small values of polarization
Variáveis cataclísmicas (VCs) são sistemas binários cerrados, compostos por uma anã branca e uma anã vermelha, com transferência de matéria da secundária para o objeto compacto. As VCs onde o campo magnético na superfície da anã branca é muito intenso, B (símbolo) 1MG, são classificadas como VCs magnéticas. Nesse caso, pelo menos na região m
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 28/02/2011
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4. Optical polarimetry and modelling of the polar FL Ceti / Polarimetria óptica e modelagem da polar FL Ceti
Cataclysmics variables (CV) are binary systems of short orbital period composed by a white dwarf and a red dwarf star that fills its Roche lobe and transfers matter to the white dwarf. In polars, a particular subclass of CVs, matter follows the magnetic field lines of the white dwarf (about 10^7 Gauss on the surface) and gives rise an accretion column. Near
Publicado em: 2009
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5. Sobre a natureza dos processos físicos de aquecimento da atmosfera de estrelas do tipo solar
In the present work, we have studied the nature of the physical processes of the coronal heating, considering as basis significant samples of single and binary evolved stars, that have been achieved with the ROSAT satellite. In a total of 191 simple stars were studied, classified in the literature as giants with spectral type F, G and K. The resu
Publicado em: 2008
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6. A evolução da rotação estelar na vizinhança solar
Different studies point for an rotationage link following a
α tα relationship. The value of the α -parameter has a strong role on the evolutionary behaviour of rotation, because it indicates how strong is the spindown once stars evolve. The well known Skumanichs relation α t −1/2, which is consistent with simple theories Publicado em: 2006
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7. "Dusty Plasmas: stellar winds and the interstellar medium" / "Plasmas empoeirados: ventos estelares e o meio interestelar"
In this work, we firstly discuss the propagation of Alfvén waves in dusty plasmas found in several astrophysical environments. The wave dispersion relation is modified giving rise to new damping mechanisms. There are in the literature observational data indicating the presence of dust near the surface of cool giant and supergiant stars. We developed a stell
Publicado em: 2005
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8. Brown dwarfs: At last filling the gap between stars and planets
Until the mid-1990s a person could not point to any celestial object and say with assurance that “here is a brown dwarf.” Now dozens are known, and the study of brown dwarfs has come of age, touching upon major issues in astrophysics, including the nature of dark matter, the properties of substellar objects, and the origin of binary stars and planet
The National Academy of Sciences.