Navegação Ciências Exatas e da Terra por Assunto "Galaxies : nuclei"

Resultados 1-20 de 29

    • Active galactic nuclei signatures in Red Geyser galaxies from Gemini GMOS-IFU observations 

      Ilha, Gabriele da Silva; Riffel, Rogemar André; Ricci, Tiago Vecchi; Rembold, Sandro Barboza; Storchi-Bergmann, Thaisa; Riffel, Rogério; Roy, Namrata; Bundy, Kevin; Nemmen, Rodrigo S.; Schimoia, Jáderson da Silva; Costa, Luiz N. da (2022) [Artigo de periódico]
      Red Geysers are quiescent galaxies with galactic scale ionized outflows, likely due to low-luminosity active galactic nuclei (AGN). We used Gemini GMOS-IFU observations of the inner~1–3 kpc of nine Red Geysers selected ...

    • AGNIFS survey of local AGN : GMOS-IFU data and outflows in 30 sources 

      Dutra, Daniel Ruschel; Storchi-Bergmann, Thaisa; Müller, Allan Schnorr; Riffel, Rogemar André; Oliveira, Bruno Dall'Agnol de; Lena, Davide; Robinson, Andrew; Nagar, Neil M.; Elvis, Martin (2021) [Artigo de periódico]
      We analyse optical data cubes of the inner kiloparsec of 30 local (z ≤ 0.02) active galactic nucleus (AGN) hosts that our research group, AGNIFS, has collected over the past decade via observations with the integral field ...

    • BASS XXXI : outflow scaling relations in low redshift X-ray AGN host galaxies with MUSE 

      Kakkad, Darshan; Mallmann, Nícolas Dullius; Riffel, Rogério; Urry, C. Megan (2022) [Artigo de periódico]
      Ionized gas kinematics provide crucial evidence of the impact that active galactic nuclei (AGNs) have in regulating star formation in their host galaxies. Although the presence of outflows in AGN host galaxies has been ...

    • Chemical abundance calibrations for the narrow-line region of active galaxies 

      Storchi-Bergmann, Thaisa; Schmitt, Henrique Roberto; Calzetti, Daniela; Kinney, Anne Louise (1998) [Artigo de periódico]
      We investigate two chemical abundance calibrations for the narrow-line region (NLR) of active galaxies in terms of three easily observable optical emission-line ratios, namely, [O III] λλ4959, 5007/Hβ; [N II] λλ6548, ...

    • Chemical abundances in Seyfert galaxies : IX. Helium abundance estimates 

      Dors Júnior, Oli Luiz; Valerdi, Mabel; Freitas-Lemes, Priscila; Krabbe, Angela Cristina; Riffel, Rogemar André; Amôres, Eduardo Brescansin de; Riffel, Rogério; Armah, Mark; Santos, Adriano Francisco Monteiro dos; Oliveira Junior, Celso Benedito de (2022) [Artigo de periódico]
      For the first time, the helium abundance relative to hydrogen (He/H), which relied on direct measurements of the electron temperature, has been derived in the narrow line regions (NLRs) from a local sample of Seyfert 2 ...

    • Chemical abundances in Seyfert galaxies : VII. Direct abundance determination of neon based on optical and infrared emission lines 

      Armah, Mark; Dors Júnior, Oli Luiz; Aydar, Catarina; Cardaci, Mónica V.; Hägelle, Guillermo Federico; Feltre, Anna; Riffel, Rogério; Riffel, Rogemar André; Krabbe, Angela Cristina (2021) [Artigo de periódico]
      For the first time, neon abundance has been derived in the narrow line region from a sample of Seyfert 2 nuclei. In view of this, we compiled from the literature fluxes of optical and infrared (IR) narrow emission lines ...

    • Chemical abundances in Seyfert galaxies : X. sulphur abundance estimates 

      Dors Júnior, Oli Luiz; Valerdi, Mabel; Riffel, Rogemar André; Riffel, Rogério; Cardaci, Mónica V.; Hägelle, Guillermo Federico; Armah, Mark; Revalski, Mitchell; Flury, Sophia; Freitas-Lemes, Priscila; Amôres, Eduardo Brescansin de; Krabbe, Angela Cristina; Binette, Luc; Feltre, Anna; Storchi-Bergmann, Thaisa (2023) [Artigo de periódico]
      For the first time, the sulphur abundance relative to hydrogen (S/H) in the narrow-line regions of a sample of Seyfert 2 nuclei (Sy 2s) has been derived via direct estimation of the electron temperature. Narrow emission-line ...

    • Circumnuclear star formation in active galaxies 

      Storchi-Bergmann, Thaisa; Rodriguez-Ardila, Alberto; Schmitt, Henrique Roberto; Wilson, Andrew S.; Baldwin, Jack A. (1996) [Artigo de periódico]
      We study the gas kinematics and chemical abundances in the inner regions of six galaxies with active galactic nuclei. The galaxies were selected for having star-forming regions in rings or spirals within a few kiloparsecs ...

    • Circumnuclear stellar population, morphology, and environment of Seyfert 2 galaxies : an evolutionary scenario 

      Storchi-Bergmann, Thaisa; González Delgado, Rosa M.; Schmitt, Henrique Roberto; Fernandes Junior, Roberto Cid; Heckman, Timothy M. (2001) [Artigo de periódico]
      We investigate the relation between the characteristics of the circumnuclear stellar population and both the galaxy morphology and the presence of close companions for a sample of 35 Seyfert 2 nuclei. Fifteen galaxies ...

    • A comparison of radio axis with host galaxy plane axis in Seyfert galaxies 

      Schmitt, Henrique Roberto; Kinney, Anne Louise; Storchi-Bergmann, Thaisa; Antonucci, Robert (1997) [Artigo de periódico]
      We use the radio axis as an indicator of the orientation of the obscuring torus in Seyfert galaxies and analyze the di†erence between the position angles of extended radio structures and host galaxy major axis of Seyfert ...

    • Empirical diagnostics of the starburst-AGN connection 

      Fernandes Junior, Roberto Cid; Heckman, Timothy M.; Schmitt, Henrique Roberto; González Delgado, Rosa M.; Storchi-Bergmann, Thaisa (2001) [Artigo de periódico]
      We examine a representative sample of 35 Seyfert 2 nuclei. Previous work has shown that nearly half (15) of these nuclei show the direct (but difficult to detect) spectroscopic signature at optical/near-UV wavelengths of ...

    • Evidence for a precessing accretion disk in the nucleus of NGC 1097 

      Storchi-Bergmann, Thaisa; Eracleous, Michael; Ruiz, Maria Teresa; Livio, Mario; Wilson, Andrew S.; Filippenko, Alexei V. (1997) [Artigo de periódico]
      We present new spectroscopic observations of the LINER (and now Seyfert 1) nucleus of NGC 1097, and discuss the evolution of its broad, double-peaked Balmer lines. When originally discovered in 1991, the red peak of the ...

    • Gas inflows in the polar ring of NGC 4111 : the birth of an AGN 

      Roier, Gabriel Roberto Hauschild; Storchi-Bergmann, Thaisa; McDermid, Richard; Walsh, Jonelle; Tan, Joanne; Cohn, Jonathan; Krajnovic, Davor; Greene, Jenny E.; Valluri, Monica; Gültekin, Kayhan; Thater, Sabine; Ven, Glenn van de; Gebhardt, Karl; Lützgendorf, Nora; Boizelle, Benjamin; Ma, Chung-Pei; Barth, Aaron J. (2022) [Artigo de periódico]
      We have used Hubble Space Telescope (HST) images, SAURON Integral Field Spectroscopy (IFS), and adaptative optics assisted Gemini NIFS near-infrared K-band IFS to map the stellar and gas distribution, excitation and ...

    • Gemini NIFS survey of feeding and feedback in nearby active galaxies V. Molecular and ionized gas kinematics 

      Bianchin, Marina; Riffel, Rogemar André; Storchi-Bergmann, Thaisa; Riffel, Rogério; Dutra, Daniel Ruschel; Harrison, Chris; Hahn, Luis Gabriel Dahmer; Mainieri, Vincenzo; Schönell Júnior, Astor João; Dametto, Natacha Zanon (2022) [Artigo de periódico]
      We study the gas distribution and kinematics of the inner kpc of six moderately luminous (43.43 ≤ log Lbol ≤ 44.83) nearby (0.004 ≤ z ≤ 0.014) Seyfert galaxies observed with the Near-infrared Integral Field Spectrograph ...

    • A Gemini–NIFS view of the merger remnant NGC 34 

      Motter, Juliana Cristina; Riffel, Rogério; Ricci, Tiago Vecchi; Riffel, Rogemar André; Storchi-Bergmann, Thaisa; Pastoriza, Miriani Griselda; Rodriguez-Ardila, Alberto; Dutra, Daniel Ruschel; Hahn, Luis Gabriel Dahmer; Dametto, Natacha Zanon; Diniz, Marlon Rodrigo (2021) [Artigo de periódico]
      The merger remnant NGC 34 is a local luminous infrared galaxy (LIRG) hosting a nuclear starburst and a hard X-ray source associated with a putative, obscured Seyfert 2 nucleus. In this work, we use adaptive optics assisted ...

    • Hubble Space Telescope imaging of the circinus galaxy 

      Wilson, Andrew S.; Shopbell, P.L.; Simpson, Chris; Storchi-Bergmann, Thaisa; Barbosa, Fausto Kuhn Berenguer; Ward, Martin John (2000) [Artigo de periódico]
      We present a Hubble Space Telescope imaging study of the nearby (4 Mpc distant) Circinus galaxy, which contains the nearest type 2 Seyfert nucleus and prominent circumnuclear star formation. Images have been obtained in ...

    • Kinematics of the central regions of NGC 1672 

      Díaz, Rubén Joaquín; Carranza, Gustavo Jose; Dottori, Horacio Alberto; Goldes, G. (1999) [Artigo de periódico]
      We present the detailed velocity field of the central 2 kpc of the LINER galaxy NGC 1672. The iso- velocity map shows a rotational pattern with a velocity gradient of 50 km s-ˡ arcsec-ˡ in the inner 6" (1"≈ 70 pc), indicating ...

    • LLAMA : stellar populations in the nuclei of ultra-hard X-ray-selected AGN and matched inactive galaxies 

      Burtscher, Leonard; Davies, Richard I.; Shimizu, Taro; Riffel, Rogério; Rosario, David; Hicks, Erin K. S.; Lin, Ming-Yi; Riffel, Rogemar André; Schartmann, Marc; Müller, Allan Schnorr; Storchi-Bergmann, Thaisa; Xivry, Gilles Orban de; Veilleux, Sylvain (2021) [Artigo de periódico]
      The relation between nuclear (.50 pc) star formation and nuclear galactic activity is still elusive; theoretical models predict a link between the two, but it is unclear whether active galactic nuclei (AGNs) should appear ...

    • Optical properties of Peaked Spectrum radio sources 

      Nascimento, Raquel Santiago; Rodriguez-Ardila, Alberto; Hahn, Luis Gabriel Dahmer; Faria, Marcos Antonio Fonseca; Riffel, Rogério; Oliveira, Murilo Marinello Assis de; Beuchert, Tobias; Callingham, Joseph (2022) [Artigo de periódico]
      In this work, we study the optical properties of compact radio sources selected from the literature in order to determine the impact of the radio-jet in their circumnuclear environment. Our sample includes 58 Compact Steep ...

    • Spectroscopic observations of merging galaxies 

      Donzelli, Carlos J.; Pastoriza, Miriani Griselda (2000) [Artigo de periódico]
      In this paper we describe the spectroscopic and infrared properties of a sample of 25 merging galaxy pairs, selected from the catalog of Arp & Madore, and we compare them with those observed in a similar sample of interacting ...