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Related papers: Analyzing derived metallicities and ionization par…

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Context. Massive star-formation leads to enrichment with heavy elements of the interstellar medium. On the other hand, the abundance of heavy elements is a key parameter to study the star-formation history of galaxies. Furthermore, the…

We present a new model of the nebular emission from star-forming galaxies in a wide range of chemical compositions, appropriate to interpret observations of galaxies at all cosmic epochs. The model relies on the combination of…

Astrophysics of Galaxies · Physics 2016-07-22 Julia Gutkin , Stephane Charlot , Gustavo Bruzual

We have performed a differential, line-by-line, chemical abundance analysis, ultimately relative to the Sun, of nine very metal-poor main sequence halo stars, near [Fe/H]=$-$2 dex. Our abundances range from…

Solar and Stellar Astrophysics · Physics 2017-04-05 Erin O'Malley , Andrew McWilliam , Brian Chaboyer , Ian Thompson

(Abridged) Planetary nebulae (PNe) around Wolf-Rayet [WR] central stars ([WR]PNe) constitute a particular photoionized nebula class that represents about 10% of the PNe with classified central stars. We analyse deep high-resolution…

Astrophysics of Galaxies · Physics 2015-06-03 Jorge García-Rojas , Miriam Peña , Christophe Morisset , Adal Mesa-Delgado , Maria Teresa Ruiz

We study the current discrepancy between the model-predicted and measured concentrations of Fe++ and Fe3+ in ionized nebulae. We calculate a set of photoionization models, updated with the atomic data relevant to the problem, and compare…

Astrophysics · Physics 2009-11-10 Monica Rodriguez , Robert H. Rubin

We present a sample of 22 blue ($(B-V)_{AB}<0.45$), luminous ($M_{B,AB}<-18.9$), metal-poor galaxies in the $0.69<z<0.88$ redshift range, selected from the DEEP2 galaxy redshift survey. Their spectra contain the $[OIII]\lambda4363$ auroral…

Astrophysics of Galaxies · Physics 2016-08-08 José M. Pérez , Carlos Hoyos , Ángeles I. Díaz , David C. Koo , Christopher N. Willmer

The errors inherent to the use of the standard "ionization correction factor" ("i_CF") method of calculating nebular conditions and relative abundances of H, He, N, O, Ne, S, and Ar in emission line nebulae have been investigated under…

Astrophysics · Physics 2009-10-30 J. Alexander , B. Balick

With the goal of a thorough investigation of the ionised gas and its origin in early-type group-dominant galaxies, we present archival MUSE data for 18 galaxies from the Complete Local-Volume Groups Sample (CLoGS). This data allowed us to…

Astrophysics of Galaxies · Physics 2022-09-14 P. Lagos , S. I. Loubser , T. C. Scott , E. O'Sullivan , K. Kolokythas , A. Babul , A. Nigoche-Netro , V. Olivares , C. Sengupta

We compute synthetic optical and ultraviolet (UV) emission-line properties of galaxies in a full cosmological framework by coupling, in post-processing, new-generation nebular-emission models with high-resolution, cosmological zoom-in…

Astrophysics of Galaxies · Physics 2019-05-29 Michaela Hirschmann , Stéphane Charlot , Anna Feltre , Thorsten Naab , Rachel S. Somerville , Ena Choi

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

We analyze the validity of optical diagnostic diagrams relying on emission-lines ratios and in the context of classifying Active Galactic Nuclei (AGNs) according to the cosmic metallicity evolution in the redshift range 0 < z < 11.2. In…

Astrophysics of Galaxies · Physics 2023-11-27 Oli L. Dors , M. V. Cardaci , G. F. Hagele , G. S. Ilha , C. B. Oliveira , R. A. Riffel , R. Riffel , A. C. Krabbe

We report results from the third in a series of nebular abundance studies of emission-line galaxies from the KPNO International Spectroscopic Survey (KISS). Galaxies with coarse metallicity estimates of 12 + log(O/H) less than 8.2 dex were…

Astrophysics · Physics 2009-11-10 Janice C. Lee , John J. Salzer , Jason Melbourne

This Letter presents a new, remarkably simple diagnostic specifically designed to derive chemical abundances for high redshift galaxies. It uses only the H \alpha, [N II] and [S II] emission lines, which can usually be observed in a single…

Astrophysics of Galaxies · Physics 2016-02-03 Michael A. Dopita , Lisa J. Kewley , Ralph S. Sutherland , David C. Nicholls

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 offset of high redshift star-forming galaxies in the [OIII]/H$\beta$ versus [NII]/H$\alpha$ (O3N2) diagram in comparison with the local star-forming galaxy sequence is now well established. The physical origin of the shift is the…

Astrophysics of Galaxies · Physics 2016-08-31 Daniel Masters , Andreas Faisst , Peter Capak

The purpose of this work is to make available new gas-phase oxygen abundance measurements for a serendipitous sample of 27 galaxies with redshift 0.35<z<0.52. We measured the equivalent widths of the [O II]{\lambda}3727, H{\beta}, and [O…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 L. Morelli , V. Calvi , A. Cardullo , A. Pizzella , E. M. Corsini , E. Dalla Bontà

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…

The formation of the UV OH spectral lines has been investigated for a range of stellar parameters in the light of 3D hydrodynamical model atmospheres. The low atmospheric temperatures encountered at low metallicities compared with the…

Astrophysics · Physics 2009-11-06 M. Asplund , A. E. Garcia Perez

We obtained nebular spectroscopy of LMC HII regions having classified stellar populations, thereby strongly constraining the ionization input parameters. Using photoionization models, we then evaluate the performance of nebular diagnostics…

Astrophysics · Physics 2007-05-23 M. S. Oey , J. C. Shields , M. A. Dopita , R. C. Smith

ABRIDGED: NGC5253 was previously studied by our group with the aim to elucidate in detail the starburst interaction processes. Some open issues regarding the 2D structure of the main properties of the ionized gas remain to be addressed.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Ana Monreal-Ibero , Jeremy R. Walsh , Jose M. Vilchez
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