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Related papers: Analyzing derived metallicities and ionization par…

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This paper outlines a way to determine the ICF using only infrared data. We identify four line pairs, [NeIII] 36$\micron$/[NeII] 12.8$\micron$, [NeIII]~15.6$\micron$ /[NeII] 12.8$\micron$, [ArIII] 9$\micron$/[ArII] 6.9$\micron$, and [ArIII]…

We present the gas-phase oxygen abundance (O/H) for a sample of 131 star-forming galaxies at intermediate redshifts ($0.2<z<1.0$). The sample selection, the spectroscopic observations (mainly with VLT/FORS) and associated data reduction,…

In the context of observations of the rest-frame ultraviolet and optical emission from distant galaxies, we explore the emission-line properties of photoionization models of active and inactive galaxies. Our aim is to identify new…

Astrophysics of Galaxies · Physics 2016-01-20 Anna Feltre , Stephane Charlot , Julia Gutkin

We present an observational and theoretical study of the ionization fraction in several massive cores located in regions that are currently forming stellar clusters. Maps of the emission from the J = 1-> O transitions of C18O, DCO+, N2H+,…

Astrophysics · Physics 2009-10-30 Edwin A. Bergin , Rene Plume , Jonathan P. Williams , Philip C. Myers

Spectrophotometry constitutes a unique way to obtain the whole diagnostics (density, temperature, ionic abundances) of ionized gas nebulae, thus providing invaluable information about the objects where they reside. If such nebulae are in…

Astrophysics · Physics 2007-05-23 E. Perez-Montero , A. I. Diaz

We investigate the physical conditions of ionized gas in high-z star-forming galaxies using diagnostic diagrams based on the rest-frame optical emission lines. The sample consists of 701 galaxies with an Ha detection at $1.4\lesssim…

We study the ionization structure of galactic outflows in 37 nearby, star forming galaxies with the Cosmic Origins Spectrograph on the Hubble Space Telescope. We use the O I, Si II, Si III, and Si IV ultraviolet absorption lines to…

Astrophysics of Galaxies · Physics 2016-03-09 John Chisholm , Christy A. Tremonti , Claus Leitherer , Yanmei Chen , Aida Wofford

Estimates of the gas temperature in planetary nebulae obtained from the [O III] emission line ratio and from the Balmer discontinuity indicate differences reaching up to 6000 K (Liu and Danziger 1993). The [O III] temperature is commonly…

Astrophysics · Physics 2007-05-23 Lucimara P. Martins , Sueli M. M. Viegas

We present an analysis to disentangle the connection between physical quantities that characterize the conditions of ionized HII regions -- metallicity ($Z$), ionization parameter ($U$), and electron density ($n_\mathrm{e}$) -- and the…

Astrophysics of Galaxies · Physics 2019-04-10 Daichi Kashino , Akio K. Inoue

Medium-resolution spectra from 3650 angstroms to 10,000 angstroms are presented for 96 giant H II regions distributed in 20 spiral galaxies. We have calculated two separate grids of photoionization models, adopting single-star atmospheres…

Astrophysics · Physics 2009-10-30 F. Bresolin , R. C. Kennicutt , D. R. Garnett

We analysed the optical spectra of HII regions extracted from a sample of 350 galaxies of the CALIFA survey. We calculated total O/H abundances and, for the first time, N/O ratios using the semi-empirical routine HII-CHI-mistry, which,…

Although measuring the gas metallicity in galaxies at various redshifts is crucial to constrain galaxy evolutionary scenarios, only rest-frame optical emission lines have been generally used to measure the metallicity. This has prevented us…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Tohru Nagao , Roberto Maiolino , Alessandro Marconi , Hideo Matsuhara

We investigate the discrepancy between oxygen abundance estimations for narrow-line regions (NLRs) of Active Galactic Nuclei (AGNs) type Seyfert 2 derived by using direct estimations of the electron temperature (Te-method) and those derived…

Astrophysics of Galaxies · Physics 2020-07-01 O. L. Dors , R. Maiolino , M. V. Cardaci , G. F. Hagele , A. C. Krabbe , E. Perez-Montero , M. Armah

This is the third paper of a series devoted to study the properties of bars from long slit spectroscopy to understand their formation, evolution and their influence on the evolution of disk galaxies. In this work we aim to determine the gas…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 E. Florido , I. Pérez , A. Zurita , P. Sánchez-Blázquez

The spatial distribution of metals reflects, and can be used to constrain, the processes of chemical enrichment and mixing. Using PHANGS-MUSE optical integral field spectroscopy, we measure the gas phase oxygen abundances (metallicities)…

In this work, we investigated the nitrogen and oxygen abundances in a sample of galaxies with Low Ionization Nuclear Emission Regions (LINERs) in their nucleus. Optical spectroscopic data (3 600 - 10 000 {\AA}) of 40 LINERs from the Mapping…

The distribution of stellar abundances along the Galactic disk is an important constraint for models of chemical evolution and Galaxy formation. In this study we derive radial gradients of C, N, O, Mg, Al, Si, as well as S, from abundance…

Astrophysics · Physics 2009-11-10 Simone Daflon , Katia Cunha

We investigate the oxygen and nitrogen abundance distributions across the optical disks of 130 nearby late-type galaxies using around 3740 published spectra of HII regions. We use these data in order to provide homogeneous abundance…

Astrophysics of Galaxies · Physics 2015-06-19 L. S. Pilyugin , E. K. Grebel , A. Y. Kniazev

We present our parameterizations of the log([NeIII]3869/[OII]3727) (Ne3O2) and log([OIII]5007/[OII]3727) ratios as comparable and effective diagnostics of ionization parameter in star-forming galaxies. Our calibrations are based on the most…

Astrophysics of Galaxies · Physics 2015-06-17 Emily M. Levesque , Mark L. A. Richardson

We present magnesium abundances derived from high resolution spectra using several Mg I and two high excitation Mg II lines for 19 metal-poor stars with [Fe/H] values between -1.1 and +0.2. The main goal is to search for systematic…

Astrophysics · Physics 2016-08-30 Carlos Abia , Lyudmila Mashonkina
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