Active Galactic Nuclei
Mostrando 1-12 de 17 artigos, teses e dissertações.
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1. Polarización de la luz: conceptos básicos y aplicaciones en astrofísica
Abstract The astrophysics allows to understand applications about physical laws and it constitutes a powerful, didactic tool for the teaching. Concepts of the electromagnetism, such as the polarization of the light let us study different astronomical objects, such as stars, planets and galaxies. This work shows an historical revision about the polarization,
Rev. Bras. Ensino Fís.. Publicado em: 02/08/2018
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2. Espectroscopia 3D de núcleos ativos de galáxias: tratamento e análise de dados no óptico e infravermelho próximo / 3D spectroscopy of active galactic nuclei: treating and analysing data in the optical and near infrared.
Nesse trabalho, foi feito o tratamento e a análise de cubos de dados de 8 núcleos ativos de galáxias próximos, no óptico e no infravermelho. O tratamento e a análise de todos os cubos de dados foram feitos utilizando-se uma série de metodologias específicas, muitas das quais foram desenvolvidas nos últimos anos pelo grupo de trabalho do autor. A an�
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 28/06/2012
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3. Formação e evolução de galáxias: populações estelares na Via Láctea, galáxias elípticas e propriedades de galáxias em grupos / Galaxy Formation and Evolution: From the Milky Way to Galaxies in Groups
Understanding the way galaxies form and evolve throughout the cosmic time remains one of the greatest challenges of modern cosmology. Several processes are known to play a role in the formation of galaxies, such as feedback from supernovae and active galactic nuclei, chemical and dynamical evolution and environmental effects. This thesis encompasses these pr
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 13/03/2012
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4. Escoamento acretivo como origem da emissão nuclear na galáxia NGC 1097
NGC1097 é uma galáxia espiral a uma distância de 14.5 Mpc, com um núcleo LINER (do inglês Low-Ionization Nuclear Emission Region) de baixa luminosidade, a partir do qual foi descoberta em 1991 emissão larga de duplo pico nas linhas de Balmer do hidrogênio. O perfil destas linhas mostrou-se, em trabalho anterior, ser bem reproduzido por um modelo de di
Publicado em: 2007
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5. Models of disks and other self-gravitating structures in general relativity / Modelos de discos e outras estruturas auto-gravitantes em relatividade geral
Exact solutions of Einstein field equations that represent space-times with disklike matter distributions are constructed using the inverse method (image method). These solutions include static thin perfect uid disks with and without halos, static thin charged perfect uid disks and models of thin charged dust disks. New solutions in various coordinate system
Publicado em: 2006
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6. Influence of the black hole rotation on accretion discs and jets in active galaxies: the case of NGC 1068
Although we do not observe directly black holes in the Universe, their presence has been inferred in several astrophysical systems, from galactic to extragalactic scales. In this work, we will restrict our focus in the possible signatures of the presence of Kerr black holes in active galactic nuclei, one of the most powerful sources in the Universe. Particul
Brazilian Journal of Physics. Publicado em: 2005-12
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7. Relativistic jets and accretion phenomena associated with galactic and extragalactic black holes
More than a dozen binary star systems hosting stellar-mass black holes have been discovered in our galaxy. Some of them eject collimated relativistic jets with apparent velocities larger than the light speed. These objects have been named microquasars thanks to their similarity with the distant quasars or active nuclei of galaxies that host supermassive blac
Brazilian Journal of Physics. Publicado em: 2005-12
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8. Coherent plasma processes in active galactic nuclei
The physics of active galactic nuclei (AGN) and related objects is one of the most actively pursued areas of astrophysics. Their large luminosities over the entire electromagnetic spectrum combined with extremely short time variability has stimulated a large number of astrophysicists to propose rather unconventional ideas. A variety of radiation mechanisms s
Brazilian Journal of Physics. Publicado em: 2002-12
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9. Optical spectroscopy of obscured active galaxies / Espectroscopia óptica de galáxias ativas obscurecidas
We present in this work a study of obscured Active Galaxies which were identified by Sofia Kirhakos in 1990. She verified that surveys at the optical part of the spectrum are not efficient to identify Seyfert nuclei in galaxies observed edge-on. To overcome this difficulty she proposed a selection criterion in which sources identified by the IRAS satellite t
Publicado em: 1998
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10. Active galactic nuclei
Active galactic nuclei are the most powerful, long-lived objects in the Universe. Recent data confirm the theoretical idea that the power source is accretion into a massive black hole. The common occurrence of obscuration and outflows probably means that the contribution of active galactic nuclei to the power density of the Universe has been generally u
The National Academy of Sciences.
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11. Gravitational lensing of active galactic nuclei.
Most of the known cases of strong gravitational lensing involve multiple imaging of an active galactic nucleus. The properties of lensed active galactic nuclei make them promising systems for astrophysical applications of gravitational lensing; in particular, they show structure on scales of milliseconds of arc to tens of seconds of arc, they are variable, a
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12. Quasars and active galactic nuclei: high resolution radio imaging.