NGC 2579 and the carbon and oxygen abundance gradients beyond the solar circle

Abstract

We present deep echelle spectrophotometry of the Galactic HII region NGC 2579. The data have been taken with the Very Large Telescope Ultraviolet-Visual Echelle Spectrograph in the 3550--10400 Å range. This object, which has been largely neglected, shows however a rather high surface brightness, a high ionization degree and is located at a galactocentric distance of 12.4 $\pm$ 0.7 kpc. Therefore, NGC 2579 is an excellent probe for studying the behaviour of the gas phase radial abundance gradients in the outer disc of the Milky Way. We derive the physical conditions of the nebula using several emission line-intensity ratios as well as the abundances of several ionic species from the intensity of collisionally excited lines. We also determine the ionic abundances of C${}^{2+}$, O${}^{+}$ and O${}^{2+}$ -- and therefore the total O abundance -- from faint pure recombination lines. The results for NGC 2579 permit to extend our previous determinations of the C, O and C/O gas phase radial gradients of the inner Galactic disc (Esteban etal. 2005) to larger galactocentric distances. We find that the chemical composition of NGC 2579 is consistent with flatten gradients at its galactocentric distance. In addition, we have built a tailored chemical evolution model that reproduces the observed radial abundance gradients of O, C and N and other observational constraints. We find that a levelling out of the star formation efficiency about and beyond the isophotal radius can explain the flattening of chemical gradients observed in the outer Galactic disc.

10 pages, 5 figures. Accepted for publication in Monthly Notices of the Royal Astronomical Society

References in corpus (55)

• The chemical composition of the Sun
• Star Formation in the Milky Way and Nearby Galaxies
• Stellar evolution with rotation VIII: Models at Z = 10^{-5} and CNO yields for early galactic evolution
• Extremely Inefficient Star Formation in the Outer Disks of Nearby Galaxies
• Some Revised Observational Constraints on the Formation and Evolution of the Galactic Disk
• Nucleosynthesis in Type Ia Supernovae
• A reappraisal of the chemical composition of the Orion nebula based on VLT echelle spectrophotometry
• The Formation and Survival of Discs in a Lambda-CDM Universe
• Effects of Supernova Feedback on the Formation of Galaxy Disks
• Very low metallicity massive star models: Pre-SN evolution and primary nitrogen production
• Resolving the electron temperature discrepancies in HII Regions and Planetary Nebulae: kappa-distributed electrons
• The flat oxygen abundance gradient in the extended disk of M83
• HII Region Metallicity Distribution in the Milky Way Disk
• The Chemical Composition of the Small Magellanic Cloud H II Region NGC 346 and the Primordial Helium Abundance
• Keck HIRES Spectroscopy of Extragalactic HII Regions: C and O Abundances from Recombination Lines
• On the abundance discrepancy problem in HII regions
• Elemental Abundance Ratios in Stars of the Outer Galactic Disk. IV. A New Sample of Open Clusters
• Gas Metallicities in the Extended Disks of NGC 1512 and NGC 3621. Chemical Signatures of Metal Mixing or Enriched Gas Accretion?
• The localized chemical pollution in NGC 5253 revisited: Results from deep echelle spectrophotometry
• Carbon and Oxygen Galactic Gradients: Observational Values from HII Region Recombination Lines
• The Chemical Composition of the 30 Doradus Nebula Derived from VLT Echelle Spectrophotometry
• Yields of rotating stars at solar metallicity
• Carbon in Spiral Galaxies from Hubble Space Telescope Spectroscopy
• The Distribution of the Elements in the Galactic Disk II. Azimuthal and Radial Variation in Abundances from Cepheids
• Abundances of Galactic Anticenter Planetary Nebulae and the Oxygen Abundance Gradient in the Galactic Disk
• Milky Way vs Andromeda: a tale of two disks
• On the metallicity gradient of the Galactic disk
• Overlapping abundance gradients and azimuthal gradients related to the spiral structure of the Galaxy
• Temperature Bias and the Primordial Helium Abundance Determination
• Carbon Nitrogen, and Oxygen Galactic Gradients: A Solution to the Carbon Enrichment Problem
• Elemental Abundance Ratios in Stars of the Outer Galactic Disk. III. Cepheids
• On the O/H, Mg/H, Si/H and Fe/H Gas and Dust Abundance Ratios in Galactic and Extragalactic H II Regions
• Faint emission lines in the Galactic H II regions M16, M20 and NGC 3603
• Metal Transport to the Gaseous Outskirts of Galaxies
• Radiative Transfer Effects in He I Emission Lines
• The [Fe IV] Discrepancy: Constraining the Iron Abundances in Nebulae
• A photoionization modeling study of 30 Doradus: the case for small-scale chemical inhomogeneity
• Deep Echelle Spectrophotometry of S 311, a galactic H II Region Outside the Solar Circle
• Theoretical He I Emissivities in the Case B Approximation
• Origin and Evolution of the Abundance Gradient along the Milky Way Disk
• He~I Emission in the Orion Nebula and Implications for Primordial Helium Abundance
• The Abundance Gradient in the Extremely Faint Outer Disk of NGC 300
• Chemical abundances of planetary nebulae towards the direction of the galactic anticenter
• Enrichment of the ISM by metal-rich droplets and the abundance bias in HII regions
• Chemical consequences of low star formation rates: stochastically sampling the IMF
• Faint recombination lines in Galactic PNe with [WC] nucleus
• Chemical Evolution Models for Spiral Disks: the Milky Way, M31 and M33
• New results on the time variation of the radial abundance gradients from planetary nebulae
• On the Nature of the HII Regions in the Extended Ultraviolet Disc of NGC 4625
• The Structure and Metallicity Gradient in the Extreme Outer Disk of NGC 7793
• An estimate of the time variation of the abundance gradient from planetary nebulae III. O, S, Ar, and Ne: A comparison of PN samples
• Chemical abundances in the protoplanetary disk LV2 (Orion): clues to the causes of the abundance anomaly in HII regions
• Ionized gas diagnostics from protoplanetary discs in the Orion Nebula and the abundance discrepancy problem
• Multiconfiguration Dirac-Hartree-Fock energy levels and transition probabilities for 3d^5 in Fe IV
• A study of the neglected Galactic HII region NGC 2579 and its companion ESO 370-9

Cited by in corpus (48)

• PyNeb: a new tool for analyzing emission lines. I. Code description and validation of results
• The O3N2 and N2 abundance indicators revisited: improved calibrations based on CALIFA and Te-based literature data
• Understanding Galaxy Evolution through Emission Lines
• A characteristic oxygen abundance gradient in galaxy disks unveiled with CALIFA
• The MOSDEF Survey: Electron Density and Ionization Parameter at $z\sim 2.3$
• Shape of the oxygen abundance profiles in CALIFA face-on spiral galaxies
• Nebular spectroscopy: A guide on H II regions and planetary nebulae
• The shape of oxygen abundance profiles explored with MUSE: evidence for widespread deviations from single gradients
• Carbon and oxygen abundances from recombination lines in low-metallicity star-forming galaxies. Implications for chemical evolution
• Carbon and oxygen in HII regions of the Magellanic Clouds: abundance discrepancy and chemical evolution
• The Galactic radial abundance gradients of C, N, O, Ne, S, Cl and Ar from deep spectra of H II regions
• Carbon and oxygen abundance gradients in NGC300 and M33 from optical recombination lines
• The origin of the high-velocity cloud complex C
• Electron Excitation of High Dipole Moment Molecules Reexamined
• The radial abundance gradient of oxygen towards the Galactic anticentre
• Gradients of chemical abundances in the Milky Way from HII regions: distances derived from Gaia EDR3 parallaxes and temperature inhomogeneities
• 3-D gas-phase elemental abundances across the formation histories of Milky Way-mass galaxies in the FIRE simulations: initial conditions for chemical tagging
• Oxygen abundance distribution in Galactic disc
• Chemical distribution of HII regions towards the Galactic anticentre
• Density biases and temperature relations for DESIRED HII regions
• Analysis of chemical abundances in planetary nebulae with [WC] central stars. II. Chemical abundances and the abundance discrepancy factor
• On the radial abundance gradients of nitrogen and oxygen in the inner Galactic disc
• Carbon, nitrogen and oxygen abundance gradients in M101 and M31
• The Te[N II]-Te[O III] temperature relation in H II regions and the reliability of strong-line methods
• Interaction effects on galaxy pairs with Gemini/GMOS- II: Oxygen abundance gradients
• Bar effect on gas-phase abundance gradients. I. Data sample and chemical abundances
• The time evolution of the Milky Way's oxygen abundance gradient
• The radial abundance gradient of chlorine in the Milky Way
• Review of scientific topics for Millimetron space observatory
• Progressive Red Shifts in the Late-Time Spectra of Type Ia Supernovae
• Dynamics and Morphology of the Milky Way Spiral Arms from the Metallicity Distribution and Radial Mixing
• The Cocoon Nebula and its ionizing star: do stellar and nebular abundances agree?
• Helium abundances and its radial gradient from the spectra of HII regions and ring nebulae of the Milky Way
• The last 5 Gyr of Galactic chemical evolution based on H II region abundances derived from a temperature independent method
• Metallicity Measurements of Gamma-Ray Burst and Supernova Explosion Sites: Lessons from HII regions in M31
• Dispersal timescale of protoplanetary disks in the low-metallicity young cluster Dolidze 25
• Photoionized Herbig-Haro objects in the Orion Nebula through deep high-spectral resolution spectroscopy III: HH514
• LAMOST Medium-Resolution Spectral Survey of Galactic Nebula (LAMOST MRS-N): An overview of Scientific goals and Survey plan
• Open cluster Dolidze 25: Stellar parameters and the metallicity in the Galactic Anticentre
• M101: Spectral Observations of HII Regions and Their Physical Properties
• Gas-phase Fe/O and Fe/N abundances in Star-Forming Regions. Relations between nucleosynthesis, metallicity and dust
• Metallicities in the Outer Regions of Spiral Galaxies
• Deep Narrowband Photometry of the M101 Group: Strong-Line Abundances of 720 HII Regions
• The Trace of the CNO Cycle in the Ring Nebula NGC6888
• Thermal Pressure in Diffuse H2 Gas Measured by Herschel [C II] Emission and FUSE UV H2 Absorption
• Deep high spectral resolution spectroscopy and chemical composition of ionized nebulae
• Metallicity gradients in M31, M33, NGC 300 and the Milky Way using abundances of different elements
• The ADF and the t${}^2$ formalism in H II regions based on the upper mass limit of the IMF for the MW