NGC 6778: Strengthening the link between extreme abundance discrepancy factors and central star binarity in planetary nebulae

Abstract

We present new optical spectra of the nearby, bright, planetary nebula NGC 6778. The nebula has been known to emit strong recombination lines for more than 40 years but this is the first detailed study of its abundances. Heavy element abundances derived from recombination lines are found to exceed those from collisionally excited lines by a factor of ~20 in an integrated spectrum of the nebula, which is among the largest known abundance discrepancy factors. Spatial analysis of the spectra shows that the abundance discrepancy factor is strongly, centrally peaked, reaching ~40 close to the central star. The central star of NGC 6778 is known to be a short period binary, further strengthening the link between high nebular abundance discrepancy factors and central star binarity.

11 pages, 5 figures, 6 tables. Accepted for publication in the main journal of MNRAS

References in corpus (9)

• On the abundance discrepancy problem in HII regions
• Carbon and oxygen abundances from recombination lines in low-metallicity star-forming galaxies. Implications for chemical evolution
• Binarity and the abundance discrepancy problem in planetary nebulae
• Chemical abundances for Hf 2-2, a planetary nebula with the strongest known heavy element recombination lines
• The double-degenerate, super-Chandrasekhar nucleus of the planetary nebula Henize 2-428
• A planetary nebula around nova V458 Vul undergoing flash ionization
• The post-common envelope central stars of the planetary nebulae Henize 2-155 and Henize 2-161
• A radial velocity survey for post-common-envelope Wolf-Rayet central stars of planetary nebulae: First results and discovery of the close binary nucleus of NGC 5189
• The planetary nebula IPHASXJ211420.0+434136 (Ou5): insights into common-envelope dynamical and chemical evolution

Cited by in corpus (49)

• Binary stars as the key to understanding planetary nebulae
• Nebular spectroscopy: A guide on H II regions and planetary nebulae
• Confirmation of the link between central star binarity and extreme abundance discrepancy factors in planetary nebulae
• ALFA: an automated line fitting algorithm
• Density biases and temperature relations for DESIRED HII regions
• Imaging the elusive H-poor gas in the high ADF planetary nebula NGC 6778
• Binary Central Stars of Planetary Nebulae Discovered Through Photometric Variability V: The Central Stars of HaTr 7 and ESO 330-9
• MUSE spectroscopy of planetary nebulae with high abundance discrepancies
• Planetary nebulae that cannot be explained by binary systems
• The short orbital period binary star at the heart of the planetary nebula M 3-1
• The planetary nebula IC 4776 and its post-common-envelope binary central star
• Forming H-shaped and barrel-shaped nebulae with interacting jets
• Abell 30 -- A Binary Central Star Among the Born-Again Planetary Nebulae
• Accounting for planet-shaped planetary nebulae
• Inclined jets inside a common envelope of a triple stellar system
• Observational Constraints on the Common Envelope Phase
• Bi-abundance photoionization models of planetary nebulae: determining the amount of Oxygen in the metal rich component
• Very Large Telescope deep echelle spectroscopy of Galactic planetary nebulae NGC 6153, M 1-42 and Hf 2-2
• The formation of `columns crowns' by jets interacting with a circumstellar dense shell
• IFU spectroscopy of Southern PNe: VII Photo-ionization modelling of intermediate excitation class objects
• Shaping planetary nebulae with jets in inclined triple stellar systems
• The Kinematics of the Permitted C II $\lambda$ 6578 Line in a Large Sample of Planetary Nebulae
• The binary fraction of planetary nebula central stars: the promise of VPHAS+
• An outburst powered by the merging of two stars inside the envelope of a giant
• The post-common-envelope binary central star of the planetary nebula Ou 5: a doubly-eclipsing post-red-giant-branch system
• Spectroscopic Analysis Tool for intEgraL fieLd unIt daTacubEs (satellite): Case studies of NGC 7009 and NGC 6778 with MUSE
• Characterisation of the Planetary Nebula Tc 1 Based on VLT X-Shooter Observations
• On the role of reduced wind mass-loss rate in enabling exoplanets to shape planetary nebulae
• The ionised and molecular mass of post-common-envelope planetary nebulae. The missing mass problem
• The kinematical behaviour of ORLs and CELs in Galactic PNe
• The impact of strong recombination on temperature determination in planetary nebulae
• When Nature Tries to Trick Us
• MUSE spectroscopy of the high abundance discrepancy planetary nebula NGC 6153
• The future influence of six exoplanets on the envelope properties of their parent stars on the giant branches
• Physical properties of the very young PN Hen3-1357 (Stingray Nebula) based on multiwavelength observations
• Physical and chemical properties of Wolf-Rayet planetary nebulae
• Variable jets at the termination of the common envelope evolution
• Planetary nebulae hosting accreting white dwarfs: A possible solution for the mysterious cut-off of Planetary Nebula Luminosity Function?
• Bi-abundance ionization structure of the Wolf-Rayet planetary nebula PB 8
• Physical conditions and chemical abundances in photoionized nebulae from optical spectra
• Resonant Temperature Fluctuations in Nebulae Ionized by Short-Period Binary Stars
• Surveying Planetary Nebulae Central Stars for Close Binaries: Constraining Evolution of Central Stars Based on Binary Parameters
• Testing atomic collision theory with the two-photon continuum of astrophysical nebulae
• Imaging the elusive H-poor gas in planetary nebulae with large abundance discrepancy factors
• Detailed studies of IPHAS sources -- I. The disrupted late bipolar IPHASX J193718.6+202102
• Physical Conditions and Chemical Abundances of the Variable Planetary Nebula IC 4997
• The post-common-envelope binary central star of the planetary nebula PN G283.7-05.1: A possible post-red-giant-branch planetary nebula central star
• Gaseous abundances in planetary nebulae: What have we learned in the past five years?
• Close binary central stars and the abundance discrepancy - new extreme objects