Listar Ciencias Exactas y Naturales por tema "Meio interestelar"
Mostrando ítems 1-20 de 20
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Active galactic nuclei signatures in Red Geyser galaxies from Gemini GMOS-IFU observations
(2022) [Artículo 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 ... -
Active galactic nuclei winds as the origin of the H2 emission excess in nearby galaxies
(2020) [Artículo de periódico]In most galaxies, the fluxes of rotational H2 lines strongly correlate with star formation diagnostics [such as polycyclic aromatic hydrocarbons (PAHs)], suggesting that H2 emission from warm molecular gas is a minor ... -
Chemical abundances in Seyfert galaxies : X. sulphur abundance estimates
(2023) [Artículo 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 ... -
Delta Scuti Network observations of XX Pyx : detection of 22 pulsation modes and of short-term amplitude and frequency variations
(2000) [Artículo de periódico]We report multisite observations devoted to the main-sequence δ Scuti star XX Pyx, conducted as the 17th run of the Delta Scuti Network. Over 125 nights a total of 550 h of usable time-series photometric B- and V-filter ... -
Determining star formation rates in active galactic nuclei hosts via stellar population synthesis
(2021) [Artículo de periódico]The effect of active galactic nuclei (AGNs) feedback on the host galaxy, and its role in quenching or enhancing star formation, is still uncertain due to the fact that usual star formation rate (SFR) indicators – emission-line ... -
Estimating stellar birth radii and the time evolution of Milky Way’s ISM metallicity gradient
(2018) [Artículo de periódico]We present a semi-empirical, largelymodel-independent approach for estimatingGalactic birth radii, rbirth, for Milky Way disc stars. The technique relies on the justifiable assumption that a negative radial metallicity ... -
First detection of the 448 GHz H2O transition in space
(2017) [Artículo de periódico]We present the first detection of the ortho-H2O 423330 transition at 448 GHz in space. We observed this transition in the local (z = 0:010) luminous infrared (IR) galaxy ESO 320-G030 (IRAS F11506-3851) using the Atacama ... -
Gauging the effect of supermassive black holes feedback on quasar host galaxies
(2021) [Artículo de periódico]In order to gauge the role that active galactic nuclei play in the evolution of galaxies via the effect of kinetic feedback in nearby QSO 2’s (z ∼ 0.3), we observed eight such objects with bolometric luminosities Lbol∼1046ergs−1 ... -
High-velocity extended molecular outflow in the star-formation dominated luminous infrared galaxy ESO 320-G030
(2016) [Artículo de periódico]We analyze new high spatial resolution ( 60 pc) ALMA CO(21) observations of the isolated luminous infrared galaxy ESO 320- G030 (d = 48 Mpc) in combination with ancillary Hubble Space Telescope optical and near infrared ... -
How well do local relations predict gas-phase metallicity gradients? : results from SDSS-IV MaNGA
(2022) [Artículo de periódico]Gas-phase metallicity gradients in galaxies provide important clues to those galaxies’ formation histories. Using SDSS-IV MaNGA data, we previously demonstrated that gas metallicity gradients vary systematically and ... -
Ionized outflows in local luminous AGN : what are the real densities and outflow rates?
(2020) [Artículo de periódico]We report on the determination of electron densities, and their impact on the outflow masses and rates, measured in the central few hundred parsecs of 11 local luminous active galaxies. We show that the peak of the integrated ... -
Oxygen abundances in the narrow line regions of Seyfert galaxies and the metallicity–luminosity relation
(2023) [Artículo de periódico]We present oxygen abundances relative to hydrogen (O/H) in the narrow line regions (NLRs) gas phases of Seyferts 1 (Sy 1s) and Seyferts 2 (Sy 2s) active galactic nuclei (AGNs). We used fluxes of the optical narrow emission ... -
Planetary nebulae and the ionization of the interstellar medium in galaxies
(2022) [Artículo de periódico]We discuss the role of planetary nebulae and their progeny in galaxy context in terms of ionization of the galaxy interstellar medium. This regards ionized gas outside the disk of spiral galaxies, the diffuse ionized medium ... -
Precessing winds from the nucleus of the prototype Red Geyser?
(2019) [Artículo de periódico]Supermassive black holes (SMBHs) are present at the centre of most galaxies, with the related mass accretion processes giving origin to outflows in active galactic nuclei (AGNs). It has been presumed that only intense winds ... -
The AGNIFS survey : distribution and excitation of the hot molecular and ionized gas in the inner kpc of nearby AGN hosts
(2021) [Artículo de periódico]We use the Gemini NIFS instrument to map the H22.1218μm and Brγ flux distributions in the inner 0.04–2 kpc of a sample of 36 nearby active galaxies (0.001 ≲ z ≲ 0.056) at spatial resolutions from 4 to 250 pc. We find ... -
The bright blue side of the night sky : Spectroscopic survey of bright and hot (pre-) white dwarfs
(2023) [Artículo de periódico]We report on the spectroscopic confirmation of 68 new bright (G = 13.5–17.2 mag) and blue (pre-)white dwarfs (WDs). This finding has allowed us to almost double the number of the hottest (Teff ≥ 60 kK) known WDs brighter ... -
The need for multicomponent dust attenuation in modeling nebular emission : constraints from SDSS-IV MaNGA
(2023) [Artículo de periódico]A fundamental assumption adopted in nearly every extragalactic study that analyzes optical emission lines is that the attenuation of different emission lines can be described by a single attenuation curve, scaled by a ... -
The OH Megamaser galaxy IRAS11506−3851 : an AGN and star formation revealed by multiwavelength observations
(2020) [Artículo de periódico]We present Gemini Multi-Object Spectrograph (GMOS) Integral Field Unit (IFU), Hubble Space Telescope (HST), and Very Large Array (VLA) observations of the OH Megamaser (OHM) galaxy IRAS 11506−3851. The HST images reveal ... -
Variations in the 6.2 μm emission profile in starburst-dominated galaxies : a signature of polycyclic aromatic nitrogen heterocycles (PANHs)?
(2018) [Artículo de periódico]Analyses of the polycyclic aromatic hydrocarbon (PAH) feature profiles, especially the 6.2 μm feature, could indicate the presence of nitrogen incorporated in their aromatic rings. In thiswork, 155 predominantly ... -
What drives the velocity dispersion of ionized gas in star-forming galaxies?
(2019) [Artículo de periódico]We analyse the intrinsic velocity dispersion properties of 648 star-forming galaxies observed by the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, to explore the relation of intrinsic gas velocity ...