Resonant temperature fluctuations in nebulae ionized by short-period binary stars

Bautista, M. A.; Ahmed, Ehab Elsayed Elhoussieny

doi:10.48550/arxiv.1709.07945

Cited by 2 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, if the recombination lines of oxygen are emitted in cold knots formed in a nova-like outburst, recombination of S + would not be expected to significantly affect the [S ii] density diagnostic. The difference in abundance discrepancies between second and third row elements also rules out any mechanism for extreme abundance discrepancies that assumes a chemically homogeneous gas; temperature fluctuations (Peimbert 1967, Bautista & Ahmed 2017, quasi-neutral X-ray irradiated regions (Ercolano 2009) and κ-distributed electrons (Nicholls et al 2012) could not account for this, although they could still potentially account for non-extreme adfs in H ii regions and PNe. This finding also suggests that an [O ii] density significantly exceeding the [S ii] density may be used to infer an extreme-adf nebula and hence a close binary central star, even if recombination lines are not detected.…”

Section: Electron Densitymentioning

confidence: 99%

“…Mechanisms proposed for the discrepancy include temperature fluctuations in a chemically homogeneous gas (Peimbert 1967), abundance gradients (Torres- Peimbert et al 1990), density fluctuations (Viegas & Clegg 1994), Xray illumination of quasi-neutral material (Ercolano 2009), hydrogen-deficient clumps (Liu et al 2000), non-thermal electron energy distributions (Nicholls et al 2012) and most recently resonant temperature fluctuations caused by varying ionization fields in nebulae with binary central stars (Bautista & Ahmed 2017). Strong indirect evidence for hydrogen-deficient material has been found in a number of objects, and such material is directly observed in a small number of unusual planetary nebulae such as Abell 30 (Wesson et al 2003) and Abell 58 (Wesson et al 2008).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Confirmation of the link between central star binarity and extreme abundance discrepancy factors in planetary nebulae

Wesson

Jones

García‐Rojas

et al. 2018

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

It has recently been noted that there seems to be a strong correlation between planetary nebulae with close binary central stars, and highly enhanced recombination line abundances. We present new deep spectra of seven objects known to have close binary central stars, and find that the heavy element abundances derived from recombination lines exceed those from collisionally excited lines by factors of 5-95, placing several of these nebulae among the most extreme known abundance discrepancies. This study nearly doubles the number of nebulae known to have a binary central star and an extreme abundance discrepancy.A statistical analysis of all nebulae with measured recombination line abundances reveals no link between central star surface chemistry and nebular abundance discrepancy, but a clear link between binarity and the abundance discrepancy, as well as an anticorrelation between abundance discrepancies and nebular electron densities: all nebulae with a binary central star with a period of less than 1.15 d have an abundance discrepancy factor exceeding 10, and an electron density less than ∼1000 cm −3 ; those with longer period binaries have abundance discrepancy factors less than 10 and much higher electron densities. We find that [O ii] density diagnostic lines can be strongly enhanced by recombination excitation, while [S ii] lines are not.These findings give weight to the idea that extreme abundance discrepancies are caused by a nova-like eruption from the central star system, occuring soon after the common-envelope phase, which ejects material depleted in hydrogen, and enhanced in CNONe but not in third-row elements.

show abstract

Section: Electron Densitymentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Confirmation of the link between central star binarity and extreme abundance discrepancy factors in planetary nebulae

Wesson

Jones

García‐Rojas

et al. 2018

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

show abstract

“…jordansp@ing.iac.es djones@iac.es rw@nebulousresearch.org jogarcia@iac.es 1980), hydrogen-deficient knots (Liu et al 2000), and orbitally-induced temperature resonances (Bautista & Ahmed 2017). Recently, a link between these high abundance discrepancy PNe and the binarity of their central stars has become evident (Wesson et al 2018).…”

Section: Introductionmentioning

confidence: 99%

Abundance Analysis of the J4 Equatorial Knot of the Born-again Planetary Nebula A30

Simpson,

Jones,

Wesson

et al. 2022

Preprint

View full text Add to dashboard Cite

Abell 30 belongs to a class of planetary nebulae identified as 'born-again', containing dense, hydrogenpoor ejecta with extreme abundance discrepancy factors, likely associated with a central binary system. We present intermediate-dispersion spectroscopy of one such feature -the J4 equatorial knot. We confirm the apparent physical and chemical segregation of the polar and equatorial knots observed in previous studies, and place an upper limit on the abundance discrepancy factor for O 2+ of 35, significantly lower than that of the polar knots. These findings further reinforce the theory that the equatorial and polar knots originate from different events.

show abstract

Resonant temperature fluctuations in nebulae ionized by short-period binary stars

Cited by 2 publications

References 0 publications

Confirmation of the link between central star binarity and extreme abundance discrepancy factors in planetary nebulae

Confirmation of the link between central star binarity and extreme abundance discrepancy factors in planetary nebulae

Abundance Analysis of the J4 Equatorial Knot of the Born-again Planetary Nebula A30

Contact Info

Product

Resources

About