Atomic Data Assessment with PyNeb

Abstract

PyNeb is a Python package widely used to model emission lines in gaseous nebulae. We take advantage of its object-oriented architecture, class methods, and historical atomic database to structure a practical environment for atomic data assessment. Our aim is to reduce the uncertainties in parameter space (line-ratio diagnostics, electron density and temperature, and ionic abundances) arising from the underlying atomic data by critically selecting the PyNeb default datasets. We evaluate the questioned radiative-rate accuracy of the collisionally excited forbidden lines of the N- and P-like ions (O II, Ne IV, S II, Cl III, and Ar IV), which are used as density diagnostics. With the aid of observed line ratios in the dense NGC 7027 planetary nebula and careful data analysis, we arrive at emissivity-ratio uncertainties from the radiative rates within 10\%, a considerable improvement over a previously predicted 50\%. We also examine the accuracy of an extensive dataset of electron-impact effective collision strengths for the carbon isoelectronic sequence recently published. By estimating the impact of the new data on the pivotal temperature diagnostics of [N II] and [O III] and by benchmarking the collision strength with a measured resonance position, we question their usefulness in nebular modeling. We confirm that the effective-collision-strength scatter of selected datasets for these two ions does not lead to uncertainties in the temperature diagnostics larger than 10\%.

arXiv commentpublished in Atoms MDPI

References in corpus (20)

• PyNeb: a new tool for analyzing emission lines. I. Code description and validation of results
• CHIANTI - An atomic database for Emission Lines. Version 8
• CHIANTI - an atomic database for emission lines - Paper XV: Version 9, improvements for the X-ray satellite lines
• Nebular spectroscopy: A guide on H II regions and planetary nebulae
• Collision Strengths for [O III] Optical and Infrared Lines
• Measuring nebular temperatures: the effect of new collision strengths with equilibrium and kappa-distributed electron energies
• Integrated spectrum of the planetary nebula NGC 7027
• Theoretical calculations of the HI, HeI and HeII free-bound continuou emission spectra
• Improved collision strengths and line ratios for forbidden [O III] far-infrared and optical lines
• Planetary nebulae and HII regions in the spiral galaxy NGC 300. Clues on the evolution of abundance gradients and on AGB nucleosynthesis
• High Resolution Photoexcitation Measurements Exacerbate the Long-Standing Fe XVII Oscillator Strength Problem
• Discovery of Rubidium, Cadmium, and Germanium Emission Lines in the Near-Infrared Spectra of Planetary Nebulae
• Recombination coefficients for O II lines in nebular conditions
• Atomic data for S II - Toward Better Diagnostics of Chemical Evolution in High-redshift Galaxies
• Neutron-Capture elements in planetary nebulae: first detections of near-Infrared [Te III] and [Br V] emission lines
• The impact of atomic data selection on nebular abundance determinations
• Bootstrapping dielectronic recombination from second-row elements and the Orion Nebula
• Testing the existence of non-Maxwellian electron distributions in H II regions after assessing atomic data accuracy
• Identification of Near-Infrared [Se III] and [Kr VI] Emission Lines in Planetary Nebulae
• R-matrix electron-impact excitation data for the C-like iso-electronic sequence

Cited by in corpus (23)

• CHIANTI -- an atomic database for emission lines -- Paper XVI: Version 10, further extensions
• CLASSY IV: Exploring UV diagnostics of the interstellar medium in local high-$z$ analogs at the dawn of the JWST era
• Ionization correction factors and dust depletion patterns in giant HII regions
• Density biases and temperature relations for DESIRED HII regions
• Observable and ionizing properties of star-forming galaxies with very massive stars and different IMFs
• Atomic Data Assessment with PyNeb: Radiative and Electron Impact Excitation Rates for [Fe II] and [Fe III]
• A $\sim$15 kpc outflow cone piercing through the halo of the blue compact metal-poor galaxy SBS0335-052
• Spectroscopic Analysis Tool for intEgraL fieLd unIt daTacubEs (satellite): Case studies of NGC 7009 and NGC 6778 with MUSE
• The influence of photo-induced processes and charge transfer on carbon and oxygen in the lower solar atmosphere
• Constraints on the densities and temperature of Seyfert 2 NLR
• MUSE crowded field 3D spectroscopy in NGC 300 III. Characterizing extremely faint HII regions and diffuse ionized gas
• JADES -- The small blue bump in GN-z11: insights into the nuclear region of a galaxy at z=10.6
• The origin of the planetary nebula M 1-16. A morphokinematic and chemical analysis
• Atomic data and the density structures of planetary nebulae
• The JWST EXCELS Survey: gas-phase metallicity evolution at 2 < z < 8
• SDSS-V LVM: Resolving Physical Conditions in the Trifid Nebula
• The [S II] Spectral Images of the Planetary Nebula NGC 7009: II. Major Axis
• Appraising the Necklace: A post-common-envelope carbon dwarf inside an apparently carbon-poor planetary nebula
• Electron density distribution in HII regions in IC10
• SDSS-V LVM: A spatially resolved study of the physical conditions and the chemical abundance discrepancy in the Lagoon Nebula (M 8)
• SIGNALS of Giant HII Regions: A Spatially Resolved Analysis of NGC 604
• Dissecting NGC 3132: Tracing the mass-loss history of the southern ring planetary nebula
• SDSS-IV MaNGA: Data-Model Discrepancy in Temperature-sensitive Line Ratios for Star-forming Galaxies