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Related papers: Metallicity measurements in AGNs

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The study of chemical abundances in stars with planets is an important ingredient for the models of formation and evolution of planetary systems. In order to determine accurate abundances, it is crucial to have a reliable set of atmospheric…

Solar and Stellar Astrophysics · Physics 2010-11-05 L. Ghezzi , K. Cunha , F. X. de Araújo , V. V. Smith , S. Schuler , R. de la Reza

The stellar metallicity is a direct measure of the amount of metals present in a galaxy, as a large part of the metals lie in its stars. In this paper we investigate new stellar metallicity indicators suitable for high-z galaxies studying…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Veronica Sommariva , Filippo Mannucci , Giovanni Cresci , Roberto Maiolino , Alessandro Marconi , Tohru Nagao , Andrea Baroni , Andrea Grazian

The Nitrogen-to-Oxygen (N/O) abundance ratio is an important diagnostic of galaxy evolution since the ratio is closely tied to the growth of metallicity and the star formation history in galaxies. Estimates for the N/O ratio are…

We present results from the NIRVANDELS survey investigating the gas-phase metallicity ($\mathrm{Z}_{\mathrm{gas}}$, tracing O/H) and stellar metallicity ($Z_{\star}$, tracing Fe/H) of 33 star-forming galaxies at redshifts $2.95 < z < 3.80$.…

We measure nebular oxygen abundances for 204 emission-line galaxies with redshifts 0.3<z<1.0 in the Great Observatories Origins Deep Survey North (GOODS-N) field using spectra from the Team Keck Redshift Survey (TKRS). We also provide an…

Astrophysics · Physics 2009-11-10 Henry A. Kobulnicky , Lisa J. Kewley

The metallicity distribution in the Fornax cluster was studied with the XIS instrument onboard the Suzaku satellite. K-shell lines of O and Mg were resolved clearly, and the abundances of O, Mg, Si, S and Fe were measured with good…

The compositions of stars are a critical diagnostic tool for many topics in astronomy such as the evolution of our Galaxy, the formation of planets, and the uniqueness of the Sun. Previous spectroscopic measurements indicate a large…

We study the direct gas-phase oxygen abundance using the well-detected auroral [OIII]4363 line in the stacked spectra of a sample of local analogs of high-redshift galaxies. These local analogs share the same location as $z\sim2$…

Astrophysics of Galaxies · Physics 2021-10-25 Fuyan Bian , Lisa J. Kewley , Michael A. Dopita

Around 16% of the solar-like stars in our neighbourhood show IR-excesses due to debris discs and a fraction of them are known to host planets. We aim to determine in a homogeneous way the metallicity of a sample of stars with known debris…

Earth and Planetary Astrophysics · Physics 2015-06-04 J. Maldonado , C. Eiroa , E. Villaver , B. Montesinos , A. Mora

We investigate the Luminosity-Metallicity (L-Z) relation in the local universe (z < 0.15) using spectra of 6387 star-forming galaxies extracted from the 2dF Galaxy Redshift Survey. This sample is by far the largest to date used to perform…

Astrophysics · Physics 2009-11-10 F. Lamareille , M. Mouhcine , T. Contini , I. Lewis , S. Maddox

Given the massive spectroscopic surveys and the Gaia mission, the Milky Way has turned into a unique laboratory to be explored using abundance ratios that show a strong dependency with time. Within this framework, the data provided through…

Context: The mass-metallicity relationship (MMR) of star-forming galaxies is well-established, however there is still some disagreement with respect to its exact shape and its possible dependence on other observables. Aims: We measure the…

High quality X-ray spectra of NGC 4636 are obtained with ASCA. Theoretical models are found unable to reproduce the data in the Fe-L line region. Spectral data above 1.4 keV indicate that Mg to Si abundance ratio is $\sim 1$ solar. Assuming…

Determining the metal content of low-mass members of young associations provides a tool that addresses different issues, such as triggered star formation or the link between the metal-rich nature of planet-host stars and the early phases of…

Solar and Stellar Astrophysics · Physics 2015-05-13 V. D'Orazi , S. Randich , E. Flaccomio , F. Palla , G. G. Sacco , R. Pallavicini

We present new observations of copper and zinc abundances in 90 metal-poor stars, belonging to the metallicity range -3< [Fe/H] < -0.5. The present study is based on high resolution spectroscopic measurements collected at the Haute Provence…

Astrophysics · Physics 2009-11-07 T. V. Mishenina , V. V. Kovtyukh , C. Soubiran , C. Travaglio , M. Busso

We derive the first luminosity-metallicity relation for a large objectively selected sample of local galaxy pairs and we compare the pairs LZ relation with the relation for the Nearby Field Galaxy Survey (NFGS). Galaxy pair members with…

Astrophysics · Physics 2008-11-26 L. J. Kewley , M. J. Geller , E. J. Barton

We measure the metal abundance ratios in the X-ray photoionized gas located near the narrow line region of a sample of Seyfert 2 AGN. The high-resolution X-ray spectra observed with the Chandra high- and low-energy transmission grating…

Astrophysics · Physics 2017-08-23 Mario A. Jimenez-Garate , Toan Khu

Using more than 100 galaxies in the MUSE Ultra Deep Field with spectroscopy from the Hubble Space Telescope's Wide Field Camera 3 and the Very Large Telescope's Multi Unit Spectroscopic Explorer, we extend the gas-phase mass-metallicity…

We analyze optical (UV rest-frame) spectra of X-ray selected narrow-line QSOs at redshift 1.5 < z < 3.7 found in the Chandra Deep Field South and of narrow-line radio galaxies at redshift 1.2 < z < 3.8 to investigate the gas metallicity of…

Astrophysics · Physics 2009-11-11 Tohru Nagao , Roberto Maiolino , Alessandro Marconi

We present nitrogen abundance measurements based on the low-ionisation [NII]6583 emission line for 588 galaxies between 1.5<z<7.0 from the JWST Advanced Deep Extragalactic Survey (JADES). We detect the temperature-sensitive [OIII]4363…

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