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相关论文: Alpha-element abundance patterns in star-forming r…

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Aims. We study the behaviour of Cl abundance and its ratios with respect to O, S and Ar abundances in a sample of more than 200 spectra of Galactic and extragalactic H ii regions and star-forming galaxies (SFGs) of the local Universe.…

We have derived abundances of O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Fe, Ni and Ba for 43 metal-poor field stars in the solar neighbourhood with iron abundances [Fe/H] ranging from -0.4 to -3.0. Total abundance errors are estimated to about…

To study the chemical evolution across cosmic epochs, we investigate Ne, S, Cl, and Ar abundance patterns in the COS Legacy Archive Spectroscopic SurveY (CLASSY). CLASSY comprises local star-forming galaxies (0.02 < z < 0.18) with enhanced…

A detailed spectroscopic study, from lambda 3700 A to 1 um, was performed for a sample of 34 HII galaxies in order to derive fundamental parameters for their HII regions and ionizing sources, as well as gaseous metal abundances. All the…

天体物理学 · 物理学 2009-11-11 C. Kehrig , J. M. Vilchez , E. Telles , F. Cuisinier , E. Perez-Montero

We show that in order to minimize the uncertainties in the N and O abundances of low mass, low metallicity (O/H less than or equal to solar/5) emission-line galaxies, it is necessary to employ separate parameterizations for inferring Te[N…

天体物理学 · 物理学 2009-11-11 A. Nava , D. Casebeer , R. B. C. Henry , D. Jevremovic

The infrared (IR) range is extremely useful in the context of chemical abundance studies of the gas-phase interstellar medium (ISM) due to the large variety of ionic species traced in this regime, the negligible effects from dust…

We present emission line strengths, abundances, and element ratios (X/O for Ne, S, Cl, and Ar) for a sample of 38 Galactic disk planetary nebulae (PNe) consisting primarily of Peimbert classification Type I. Spectrophotometry for these PNe…

太阳与恒星天体物理 · 物理学 2015-05-18 J. B. Milingo , K. B. Kwitter , R. B. C. Henry , S. P. Souza

(abridged) We present deep spectroscopy of a large sample of low-metallicity emission-line galaxies. The main goal of this study is to derive element abundances in these low-metallicity galaxies. We analyze 121 VLT spectra of HII regions in…

宇宙学与河外天体物理 · 物理学 2011-11-08 N. G. Guseva , Y. I. Izotov , G. Stasinska , K. J. Fricke , C. Henkel , P. Papaderos

The origin of the abundance discrepancy is one of the key problems in the physics of photoionized nebula. In this work, we analize and discuss data for a sample of Galactic and extragalactic HII regions where this abundance discrepancy has…

天体物理学 · 物理学 2009-11-13 Jorge Garcia-Rojas , Cesar Esteban

We have collected from different surveys some significant spectroscopic data observed from star-forming galaxies in the local Universe. The objects showing a relatively rich spectrum in number of lines from different elements were selected…

星系天体物理 · 物理学 2022-01-19 Marcella Contini

We study the physical and chemical properties of a sample of HII regions located at RG >11 kpc and present the radial distribution of abundances towards the Galaxy anticentre. We carried out optical spectroscopic observations of nine HII…

星系天体物理 · 物理学 2017-01-18 Alba Fernández-Martín , Enrique Pérez-Montero , José Manuel Vílchez , Antonio Mampaso

Photospheric C, N, and O abundances of 118 solar-analog stars were determined by applying the synthetic-fitting analysis to their spectra in the blue or near-UV region comprising lines of CH, NH, and OH molecules, with an aim of clarifying…

太阳与恒星天体物理 · 物理学 2023-02-01 Yoichi Takeda

We present a reassessment of the radial abundance gradients of C, N, O, Ne, S, Cl and Ar in the Milky Way using deep spectra of 33 H II regions gathered from the literature, covering Galactocentric distances from 6 to 17 kpc. The distances…

For the first time, the argon abundance relative to hydrogen abundance (Ar/H) in the narrow line region of a sample of Seyfert 2 nuclei has been derived. In view of this, optical narrow emission line intensities of a sample of 64 local…

星系天体物理 · 物理学 2021-10-04 A. F. Monteiro , O. L. Dors

We present a chemical abundance distribution study in 14 $\alpha$, odd-Z, even-Z, light, and Fe-peak elements of approximately 3200 intermediate metallicity giant stars from the APOGEE survey. The main aim of our analysis is to explore the…

星系天体物理 · 物理学 2016-03-02 Keith Hawkins , Paula Jofre , Thomas Masseron , Gerry Gilmore

Differential enrichment between $\alpha$- and Fe-peak elements is known to be strongly connected with the shape of the star formation history (SFH), the star formation efficiency (SFE), the inflow and outflow of material, and even the shape…

We present an analysis of eight star-forming galaxies with $\langle z \rangle = 4.0$ from the JWST EXCELS survey for which we obtain robust chemical abundance estimates for the $\alpha$-elements O, Ne and Ar. The $\alpha$-elements are…

The atmospheric parameters and abundances of Mg, Si, Ca, and Ti have been determined for 20 stars using the Gaia DR2 parallaxes, high-resolution spectra, and the non-local thermodynamic equilibrium (non-LTE) line formation modeling. A…

太阳与恒星天体物理 · 物理学 2019-09-04 Lyudmila Mashonkina , Maria Neretina , Tatyana Sitnova , Yuri Pakhomov

We derived a bi-dimensional calibration between the emission line ratios R23=([O II]3726+3729+[O II]4959+5007)/Hb, P=[([O II]4959+5007)/Hb]/R23 and the oxygen abundance relative to hydrogen (O/H) in the gas phase of Seyferts 1 and 2 nuclei.…

星系天体物理 · 物理学 2021-07-27 Dors , O. L

Context. Elemental abundances are of prime importance to help us reconstruct the origin and evolution of stars and galaxies in our Universe. Sulfur abundances have not been as heavily studied as other elements, so some details regarding its…

太阳与恒星天体物理 · 物理学 2020-02-26 Ana Rita Costa Silva , Elisa Delgado Mena , Maria Tsantaki
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