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Related papers: A new approach to the solar oxygen abundance probl…

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Estimates of the bulk metal abundance of the Sun derived from the latest generation of model atmospheres are significantly lower than the earlier standard values. In Paper I we demonstrated that a low solar metallicity is inconsistent with…

Astrophysics · Physics 2009-10-06 M. H. Pinsonneault , Franck Delahaye

We propose two statistical methods to derive oxygen abundances in HII regions and star forming galaxies and calibrate them with a sample of several hundred giant HII regions in spiral and blue compact galaxies as well as of galaxies from…

Astrophysics · Physics 2009-11-11 Grazyna Stasinska

The new solar composition, when applied to compute a model of the Sun, leads to serious disagreement between the predictions of the model and the observations obtained by helioseismology. New measurements of the coronal Ne/O abundance ratio…

Astrophysics · Physics 2007-05-23 M. Asplund , N. Grevesse , M. Guedel , A. J. Sauval

We redetermine the abundances of all iron group nuclei in the Sun, based on neutral and singly-ionised lines of Sc, Ti, V, Mn, Fe, Co and Ni in the solar spectrum. We employ a realistic 3D hydrodynamic model solar atmosphere, corrections…

Solar and Stellar Astrophysics · Physics 2014-12-17 Pat Scott , Martin Asplund , Nicolas Grevesse , Maria Bergemann , A. Jacques Sauval

We have compared the oxygen and nitrogen abundances derived from global emission-line SDSS spectra of galaxies using (1) the Te method and (2) two recent strong line calibrations: the ON and NS calibrations. Using the Te method, anomously…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 L. S. Pilyugin , J. M. Vilchez , L. Mattsson , T. X. Thuan

A key goal of the Solar Orbiter mission is to connect elemental abundance measurements of the solar wind enveloping the spacecraft with EUV spectroscopic observations of their solar sources, but this is not an easy exercise. Observations…

The variations of oxygen abundance and ionization parameter in HII regions are usually thought to be the dominant factors that produced variations seen in observed emission line spectra. However, if and how these two quantities are…

We present an adapted version of the code HII-CHI-Mistry-UV (P\'erez-Montero & Amor\'in 2017) to derive chemical abundances from emission lines in the ultraviolet, for use in narrow line regions (NLR) of Active Galactic Nuclei (AGN). We…

We have derived the oxygen abundance for a sample of nearby galaxies in the Data Release 5 of the Sloan Digital Sky Survey (SDSS) which possess at least two independent spectra of one or several HII regions with a detected [OIII]4363…

Astrophysics · Physics 2009-11-13 L. S. Pilyugin , T. X. Thuan

We report on non-LTE Ne abundances for a sample of B-type stellar members of the Orion Association. The abundances were derived by means of non-LTE fully metal-blanketed model atmospheres and extensive model atoms with updated atomic data.…

Astrophysics · Physics 2009-11-11 Katia Cunha , Ivan Hubeny , Thierry Lanz

We performed a compilation of more than 1000 published spectra of HII regions in spiral galaxies. The oxygen and nitrogen abundances in each HII region were recomputed in a homogeneous way, using the P-method. The radial distributions of…

Astrophysics · Physics 2009-11-10 L. S. Pilyugin , J. M. Vilchez , T. Contini

We perform a quantitative analysis of the solar composition problem by using a statistical approach that allows us to combine the information provided by helioseimic and solar neutrino data in an effective way. We include in our analysis…

Solar and Stellar Astrophysics · Physics 2015-06-18 F. L. Villante , A. M. Serenelli , F. Delahaye , M. H. Pinsonneault

The OI 777 nm triplet is a key diagnostic of oxygen abundances in the atmospheres of FGK-type stars; however it is sensitive to departures from local thermodynamic equilibrium (LTE). The accuracy of non-LTE line formation calculations has…

Solar and Stellar Astrophysics · Physics 2018-10-30 A. M. Amarsi , P. S. Barklem , M. Asplund , R. Collet , O. Zatsarinny

In the Sun, the two forbidden [OI] lines at 630 and 636 nm were previously found to provide discrepant oxygen abundances. aims: We investigate whether this discrepancy is peculiar to the Sun or whether it is also observed in other stars.…

Solar and Stellar Astrophysics · Physics 2015-06-15 Elisabetta Caffau , Hans-G. Ludwig , Jean-M. Malherbe , Piercarlo Bonifacio , Matthias Steffen , Lorenzo Monaco

The oxygen abundances for four dwarf spiral galaxies have been determined using long-slit spectroscopy. The abundances of these galaxies have not previously reported in the literature. Several HII regions were detected in each galaxy. The…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-01 A. M. Hidalgo-Gamez , D. Ramirez-Fuentes , J. J. Gonzalez

We examine the constraints imposed by helioseismic data on the solar heavy element abundances. In prior work we argued that the measured depth of the surface convection zone R_CZ and the surface helium abundance Y_surf were good metallicity…

Solar and Stellar Astrophysics · Physics 2010-05-05 F. Delahaye , M. H. Pinsonneault , L. Pinsonneault , C. J. Zeippen

We have re-evaluated empirical expressions for the abundance determination of N, O, Ne, S, Cl, Ar and Fe taking into account the latest atomic data and constructing an appropriate grid of photoionization models with state-of-the art model…

Astrophysics · Physics 2009-07-28 Y. I. Izotov , G. Stasinska , G. Meynet , N. G. Guseva , T. X. Thuan

The existing measurements of the solar neutrino flux are compared with the predictions of all models capable of reproducing the other solar observables. These predictions are supplemented by the hypothesis of neutrino oscillations with mass…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. Conforto , C. Grimani , F. Martelli , F. Vetrano

We discuss the level of agreement of a new generation of standard solar models (SSMs), Barcelona 2016 or B16 for short, with helioseismic and solar neutrino data, confirming that models implementing the AGSS09met surface abundances, based…

Solar and Stellar Astrophysics · Physics 2020-04-15 F. L. Villante , A. Serenelli

The compilation of published spectra of Galactic HII regions with available diagnostic [OIII]4363 line has been carried out. Our list contains 71 individual measurements of 13 HII regions in the range of galactocentric distances from 6.6 to…

Astrophysics · Physics 2011-05-23 L. S. Pilyugin , F. Ferrini , R. V. Shkvarun
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