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Navegação Teses de Doutorado PPGA por data do documento

Navegação Teses de Doutorado PPGA por data do documento

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  • BAELLA PAJUELO, NOBAR OCTAVIO (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2012-03-30)
    Entre as 180 estrelas simbióticas conhecidas existe um grupo especial classificado como simbióticas amarelas Tipo-S (SATS). Esses objetos apresentam uma alta velocidade radial e baixa metalicidade que correspondem a ...
  • ARAGAO HASSELMANN, PEDRO HENRIQUE (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2015-08-25)
    The two main Small Body populations, asteroids and comets, present different physical-chemical caracteristics on their surfaces. Most of the studies of their surfaces is based on the observation of integrated light from ...
  • COUTINHO DE CARVALHO, GABRIELA (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2015-09-11)
    The distribution of galaxies, provided by large astronomical surveys, makes possible detailed studies of the nature of the primordial density fluctuations and the process of structure formation in the universe. Among the ...
  • BENEDETTI ROSSI, GUSTAVO (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2016-03-01)
    After almost 25 years of the discovery of the first trans-Neptunian object (TNO), besides Pluto, more than 1930 other objects were discovered at the outer solar system. The study of those bodies can provide precious ...
  • DE ALMEIDA BRAGANCA, GUSTAVO (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2016-03-14)
    In this work, we analysed high resolution spectra of a large sample of OB stars located in the Galactic disk aimed to study the distribution of the projected stellar rotation (vseni) and the radial distribution of chemical ...
  • GONZALES DAVALOS, JORGE ALEJANDRO (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2016-05-24)
    In this work were generated synthetic spectra with shape effect, determining its spectral parameters: the center of the absorption bands, the ratio of the bands and the spectral slope. It has been shown that only the slope ...
  • PAES BENGALY JUNIOR, CARLOS ANDRE (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2016-12-16)
    In this work, we probe the validity of the cosmological isotropy hypothesis, which constitutes one of the main pillars of the Cosmological Principle, in the light of current observational data. We search for possible ...
  • DE JESUS RONDON BRICENO, EDUARDO (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2016-12-21)
    Seventeen asteroids of the main belt and three near earth asteroids have shown cometary activity. These objects have been called Active Asteroids (AA) (Jewitt, 2012). The physical source of their activity can be diverse; ...
  • MARTINS SOUTO, DIOGO (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2017-03-02)
    In this Thesis, we present the first results of a detailed chemical study of M-dwarf stars. We demonstrate that it is possible to obtain elemental abundances of up to thirteen elements (C, O, Na, Mg, Al, Si, K, Ca, Ti, V, ...
  • JEARIM PENA SUAREZ, VLADIMIR (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2017-08-10)
    ABSTRACT Using a sample of eight high resolution spectra of the red giants in the open cluster NGC 4349, we determined its atmospheric parameters and the chemical abundances of the light elements LiCNO, the refractory ...
  • BOUFLEUR, RODRIGO CARLOS (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2017-08-28)
    One of the most promising topics in modern astronomy is the discovery and characterization of extrasolar planets. Space missions dedicated to search exoplanets produced a formidable amount of data. In particular the Kepler ...
  • NASCIMENTO DE PRA, MARIO (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2017-08-30)
    Primitive asteroids are considered transitional objects between rocky and icy bodies. They are expected to present volatile-rich content, such as hydrated minerals. The hydration level can be obtained by the study of the ...
  • GONZALEZ SANCHEZ, JAVIER ERNESTO (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2018-02-26)
    The current large astronomical surveys have allowed us access to a growing quantity and quality of observational data. For this reason, it is necessary to explore different techniques to model and extract the maximum ...
  • DIAS DA SILVEIRA, MARLON (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2018-06-15)
    In this work we analyzed, using high-resolution spectroscopy, a sample of 12 single and 4 spectroscopic binary red giant stars of the open cluster NGC 2447 and another sample made up of 4 red giants stars from the open ...
  • HUANCA CONDORI, CESAR AUGUSTO (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2018-09-18)
    Abstract The stars with the B[e] phenomenon are characterized by the presence in the optical spectrum of B-type stars of: intense Balmer emission lines; permitted emission lines of singly ionized metals, e.g., Fe II; and ...
  • NEVES CAMPAGNOLO, JULIO CESAR (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2018-12-21)
    Abstract: This PhD thesis is related to Luminous Blue Variable stars (LBV), which are some of the most luminous stars and are characterized by eruptive processes that cause intense photometric and spectroscopic variability. ...
  • SANTOS DA COSTA, SIMONY (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2019-03-29)
    Abstract: Understanding the origin of the current cosmic acceleration is one of the biggest challenges in cosmology nowadays. In the context of the standard cosmological model, this acceleration is assigned to a dark energy ...
  • MARINELLO ASSIS DE OLIVEIRA, MURILO (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2019-04-12)
    Active galactic nuclei (AGN) are the most luminous astronomical objects in the sky. Different from normal galaxies, AGN are characterized by a strong luminous nucleus which can not be associated with its stars. In this ...
  • LOAIZA AGUDELO, MARYORY (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2019-06-21)
    Physical properties of starburts galaxies at low redshift: ``Lyman Break Analogs'' Lyman Break Analogs (LBAs) are starburst systems at low redshift undergoing intense and continuous processes of star formation, usually as ...
  • SAAD OLIVERA, XIMENA BEATRIZ (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Astronomia, 2019-06-27)
    bstract In this thesis, we present results about the complete characterization of dynamical parameters in three planetary systems, Kepler-46, Kepler-419 and Kepler-59, through the analysis of the transit timing variations ...