Characterizing the radial oxygen abundance distribution in disk galaxies

• Verfasst von: Zinchenko, Igor A. [VerfasserIn]
• Verfasst von: Just, Andreas [VerfasserIn]
• Verfasst von: Pilyugin, Leonid S. [VerfasserIn]
• Verfasst von: Lara-Lopez, Maritza Arlene [VerfasserIn]
• Titel: Characterizing the radial oxygen abundance distribution in disk galaxies
• Verf.angabe: I.A. Zinchenko, A. Just, L.S. Pilyugin, M.A. Lara-Lopez
• E-Jahr: 2019
• Jahr: 25 February 2019
• Umfang: 10 S.
• Fussnoten: Gesehen am 10.04.2019
• Titel Quelle: Enthalten in: Astronomy and astrophysics
• Ort Quelle: Les Ulis : EDP Sciences, 1969
• Jahr Quelle: 2019
• Band/Heft Quelle: 623(2019) Artikel-Nummer A7, 10 Seiten
• ISSN Quelle: 1432-0746
• DOI: doi:10.1051/0004-6361/201834364
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1663073392

Abstract

The relation between the radial oxygen abundance distribution (gradient) and other parameters of a galaxy such as mass, Hubble type, and a bar strength, remains unclear although a large amount of observational data have been obtained in the past years.<i>Aims<i/>. We examine the possible dependence of the radial oxygen abundance distribution on non-axisymmetrical structures (bar/spirals) and other macroscopic parameters such as the mass, the optical radius <i>R<i/><sub>25<sub/>, the color <i>g<i/> − <i>r<i/>, and the surface brightness of the galaxy. A sample of disk galaxies from the third data release of the Calar Alto Legacy Integral Field Area Survey (CALIFA DR3) is considered.<i>Methods<i/>. We adopted the Fourier amplitude <i>A<i/><sub>2<sub/> of the surface brightness as a quantitative characteristic of the strength of non-axisymmetric structures in a galactic disk, in addition to the commonly used morphologic division for A, AB, and B types based on the Hubble classification. To distinguish changes in local oxygen abundance caused by the non-axisymmetrical structures, the multiparametric mass-metallicity relation was constructed as a function of parameters such as the bar/spiral pattern strength, the disk size, color index <i>g<i/> − <i>r<i/> in the Sloan Digital Sky Survey (SDSS) bands, and central surface brightness of the disk. The gas-phase oxygen abundance gradient is determined by using the R calibration.<i>Results<i/>. We find that there is no significant impact of the non-axisymmetric structures such as a bar and/or spiral patterns on the local oxygen abundance and radial oxygen abundance gradient of disk galaxies. Galaxies with higher mass, however, exhibit flatter oxygen abundance gradients in units of dex/kpc, but this effect is significantly less prominent for the oxygen abundance gradients in units of dex/<i>R<i/><sub>25<sub/> and almost disappears when the inner parts are avoided (<i>R<i/> > 0.25<i>R<i/><sub>25<sub/>). We show that the oxygen abundance in the central part of the galaxy depends neither on the optical radius <i>R<i/><sub>25<sub/> nor on the color <i>g<i/> − <i>r<i/> or the surface brightness of the galaxy. Instead, outside the central part of the galaxy, the oxygen abundance increases with <i>g<i/> − <i>r<i/> value and central surface brightness of the disk.