Navegação Ciências Exatas e da Terra por Assunto "Dust, extinction"

Resultados 1-15 de 15

    • Dust extinction of the stellar continua in Starburst galaxies : the ultraviolet and optical extinction law 

      Calzetti, Daniela; Kinney, Anne Louise; Storchi-Bergmann, Thaisa (1994) [Artigo de periódico]
      We analyze the IUE UV and the optical spectra of 39 starburst and blue compact galaxies in order to study the average properties of dust extinction in extended regions of galaxies. The optical spectra have been obtained ...

    • Dust obscuration in starburst galaxies from near-infrared spectroscopy 

      Calzetti, Daniela; Kinney, Anne Louise; Storchi-Bergmann, Thaisa (1996) [Artigo de periódico]
      We present new observations of the near-infrared hydrogen recombination lines Paβ and Bry in the central starburst regions of 13 galaxies. The near-infrared data are supplemented with data on the optical Balmer line emission ...

    • Extinction within 10 of the Galactic centre using 2MASS 

      Dutra, Carlos Maximiliano; Santiago, Basilio Xavier; Bica, Eduardo Luiz Damiani; Barbuy, Beatriz (2003) [Artigo de periódico]
      We extract J and Ks magnitudes from the 2MASS Point Source Catalog for approximately 6×106 stars with 8 < - Ks < - 13 in order to build an AK extinction map within 10◦ of the Galactic centre. The extinction was determined ...

    • High spatial resolution of the mid-infrared emission of the Compton-thick type 2 Seyfert galaxy, Markarian 3 

      Sales, Dinalva Aires de; Dutra, Daniel Ruschel; Pastoriza, Miriani Griselda; Riffel, Rogério; Winge, Claudia (2014) [Artigo de periódico]
      The mid-infrared (MIR) spectra observed with Gemini/Michelle have been used to study the nuclear region of the Compton-thick type 2 Seyfert galaxy, Markarian 3 (Mrk 3), at a spatial resolution of ∼200 pc. No polycyclic ...

    • A method for simultaneous determination of A/sub v/ and R and applications 

      Ducati, Jorge Ricardo; Ribeiro, Daiana; Rembold, Sandro Barboza (2003) [Artigo de periódico]
      A method for the simultaneous determination of the interstellar extinction (AV) and of the ratio of total to selective extinction (R), derived from the 1989 Cardelli, Clayton, & Mathis fitting of the interstellar extinction ...

    • Multiband photometry towards the inner galactic bulge : extinction, atmospheric parameters, and metallicities 

      Santiago, Basilio Xavier; Javiel, Sandro Caldeira; Mello, Gustavo Frederico Porto de (2006) [Artigo de periódico]
      Context. We have obtained BVRI photometry for 21 stellar fields located in directions towards the central 3.5° of the Galaxy. Each field is 10 × 10 arcmin in size, and a total of ∼2 × 105 stars were measured. Aims. Previous ...

    • OMEGA – OSIRIS mapping of emission-line galaxies in A901/2 : IV. Extinction of star formation estimators with inclination 

      Wolf, Christian; Weinzirl, Timothy; Aragón-Salamanca, Alfonso; Gray, Meghan E.; Rodríguez del Pino, Bruno; Chies-Santos, Ana Leonor; Bamford, Steven Peter; Böhm, Asmus; Harborne, Katherine (2018) [Artigo de periódico]
      We study the effect of inclination on the apparent brightness of star-forming galaxies in spectral passbands that are commonly used as star formation indicators. As diagnostics we use mass-to-light ratios in three passbands: ...

    • Optical and far-infrared emission of IRAS Seyfert galaxies 

      Bonatto, Charles Jose; Pastoriza, Miriani Griselda (1997) [Artigo de periódico]
      This paper presents an analysis of moderately large samples of type 1 and 2 Seyfert galaxies through optical observations and far-infrared IRAS data, also taking into account theoretical color indices derived from dust ...

    • Reddening and age for 11 galactic open clusters from integrated spectra 

      Santos Junior, Joao Francisco Coelho dos; Bica, Eduardo Luiz Damiani (1993) [Artigo de periódico]
      We study integrated spectra of 11 Galactic open clusters in the visible and near­ infrared. We use continuum distribution and line strengths to infer reddening, age and, in some cases, metallicity. These parameters are ...

    • Strengthening the open cluster distance scale via VVV photometry 

      Majaess, Daniel J.; Turner, D. G.; Moni Bidin, Christian; Geisler, Doug; Borissova, Jura; Minniti, Dante; Bonatto, Charles Jose; Gieren, Wolfgang P.; Carraro, Giovanni; Kurtev, Radostin Georgiev; Mauro, Francesco; Chené, André-Nicolas; Forbes, Douglas; Lucas, Philip W.; Dékány, István; Saito, Roberto K.; Soto, M. (2012) [Artigo de periódico]
      Approximately 14% of known Galactic open clusters possess absolute errors ≤20% as evaluated from n ≥ 3 independent distance estimates, and the statistics for age estimates are markedly worse. That impedes such diverse ...

    • A strong correlation between circumnuclear dust and black hole accretion in early-type galaxies 

      Lopes, Ramiro Duarte Simões; Storchi-Bergmann, Thaisa; Saraiva, Maria de Fátima Oliveira; Martini, Paul (2007) [Artigo de periódico]
      We present a detailed investigation of the incidence of circumnuclear dust structure in a large, well-matched sample of early-type galaxies with and without active galactic nuclei (AGNs). All 34 early-type AGN hosts in our ...

    • The compton-thick Seyfert 2 nucleus of NGC 3281 torus constraints from the 9.7μm silicate absorption 

      Sales, Dinalva Aires de; Pastoriza, Miriani Griselda; Riffel, Rogério; Winge, Claudia; Rodriguez-Ardila, Alberto; Carciofi, Alex Cavaliéri (2011) [Artigo de periódico]
      We present mid-infrared (mid-IR) spectra of the Compton-thick Seyfert 2 galaxy NGC 3281, obtained with the Thermal-Region Camera Spectrograph at the Gemini-South telescope. The spectra present a very deep silicate absorption ...

    • The nature of the optical continuum in NGC 5128 (Centaurus a) 

      Storchi-Bergmann, Thaisa; Bica, Eduardo Luiz Damiani; Kinney, Anne Louise; Bonatto, Charles Jose (1997) [Artigo de periódico]
      We present long-slit observations of NGC 5128 in the range λλ3200-9800 Å, covering the nucleus and dust lane across the east-west direction, up to ~~ 2.2 kpc from the nucleus. The reddening-corrected continua and absorption ...

    • The origin of dust in early-type galaxies and implications for accretion onto supermassive black holes 

      Martini, Paul; Dicken, Daniel; Storchi-Bergmann, Thaisa (2013) [Artigo de periódico]
      We have conducted an archival Spitzer study of 38 early-type galaxies in order to determine the origin of the dust in approximately half of this population. Our sample galaxies generally have good wavelength coverage from ...

    • The reddening law outside the local group galaxies : the case of NGC 7552 and NGC 5236 

      Kinney, Anne Louise; Calzetti, Daniela; Bica, Eduardo Luiz Damiani; Storchi-Bergmann, Thaisa (1994) [Artigo de periódico]
      The dust reddening law from the UV to the near-IR for the extended regions of galaxies is here derived from the spectral distributions of the starburst spiral galaxies NGC 7552 and NGC 5236. The centers of these galaxies ...