Tag Archives: H II regions

Resolving the electron temperature discrepancies in H II regions and planetary nebulae: kappa-distributed electrons

David Nicholls (Australian National University, Australia) The measurement of electron temperatures and metallicities in H II regions and Planetary Nebulae has, for several decades, presented a problem: results obtained using different techniques disagree. There have been numerous attempts to explain … Continue reading

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Temperature-­based oxygen abundances in H II regions and PNe: methods and uncertainties

Mónica Rodríguez ( INAOE, Mexico) The oxygen abundances of H II regions and planetary nebulae (PNe) provide crucial clues for our understanding of galactic chemical evolution, especially when they are compared with each other and with the abundances derived for stars of … Continue reading

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On the RL/CEL discrepancy

Grazyna Stasinska Grazyna Stasinska (LUTH, Observatoire de Paris, Meudon, France) The discrepancy between abundances derived from collisionally excited lines (CEL) and recombination lines (RL) in  H II regions and planetary nebulae is still not fully understood. As I understand, the effective recombination rates … Continue reading

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Plasma diagnostics for planetary nebulae and H II regions using N II and O II

I. McNabb (1), X. Fang (1), X.-W. Liu (1,2), P.J. Storey (3) (1) Kavli Institute of Astronomy and Astrophysics at Peking University. (2) Department of Astronomy at Peking University. (3) Department of Physics and Astronomy at University College London We … Continue reading

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