Emission-line diagnostics of nearby H ii regions including interacting binary populations [PDF]
, 2018 We present numerical models of the nebular emission from H II regions around young stellar populations over a range of compositions and ages. The synthetic stellar pop- ulations include both single stars and interacting binary stars.
Lin Xiao, E. Stanway, J. J. Eldridge
semanticscholar +1 more source
Radiation Hydrodynamics of Turbulent H ii Regions in Molecular Clouds: A Physical Origin of LyC Leakage and the Associated Lyα Spectra [PDF]
Astrophysical Journal, 2019 We examine Lyman continuum (LyC) leakage through H ii regions regulated by turbulence and radiative feedback in a giant molecular cloud in the context of fully coupled radiation hydrodynamics (RHD).
K. Kakiichi, M. Gronke
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Surveying the Giant H ii Regions of the Milky Way with SOFIA. I. W51A [PDF]
Astrophysical Journal, 2019 We discuss the first results from our mid-infrared (MIR) imaging survey of Milky Way Giant H ii (GH ii) regions with our detailed analysis of W51A, which is one of the largest GH ii regions in our Galaxy.
W. Lim, J. D. De Buizer
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New calibrations for abundance determinations in H ii regions [PDF]
, 2016 Simple relations for deriving the oxygen abundance in HII regions with intensities of the three strong emission lines R_2, R_3, and N_2 (R calibration) or S_2, R_3, and N_2 (S calibration) in their spectra are suggested.
L. Pilyugin +3 more
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The Chocolate Chip Cookie Model: Dust-to-metal Ratio of H ii Regions
The Astrophysical Journal Letters, 2023 Using a sample of face-on star-forming galaxies selected from the Sloan Digital Sky Survey, we statistically derive the typical optical depth τ _cl of individual H ii regions based on the “Chocolate Chip Cookie” model of Lu et al. (2022).
Jiafeng Lu +3 more
doaj +1 more source
Searching for Galactic H ii Regions from the LAMOST Database Based on the Multihead WDCNN Model
The Astrophysical Journal Supplement Series, 2023 A H ii region is a kind of emission nebula, and more definite samples of H ii regions can help study the formation and evolution of galaxies. Hence, a systematic search for H ii regions is necessary.
Mengxin Wang +3 more
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Spectroscopy of Outlying H II Regions in Spiral Galaxies: Abundances and Radial Gradients [PDF]
, 1998 We present the results of low-dispersion optical spectroscopy of 186 H II regions spanning a range of radius in 13 spiral galaxies. Abundances for several elements (oxygen, nitrogen, neon, sulfur, and argon) were determined for 185 of the H II regions ...
L. van Zee +4 more
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Properties of H II Regions in the Centers of Nearby Galaxies [PDF]
, 1997 As part of an optical spectroscopic survey of nearby, bright galaxies, we have identified a sample of over 200 emission-line nuclei having optical spectra resembling those of giant extragalactic H II regions. Such "H II nuclei," powered by young, massive
Alexei V. Filippenko +15 more
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A VLT study of metal-rich extragalactic H II regions. I. Observations and empirical abundances [PDF]
, 2005 We have obtained spectroscopic observations from 3600 Angstrom to 9200 Angstrom with FORS at the Very Large Telescope for approximately 70 H II regions located in the spiral galaxies NGC 1232, NGC 1365, NGC 2903, NGC 2997 and NGC 5236.
Bresolin, Fabio +3 more
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Non-thermal emission from cosmic rays accelerated in H II regions [PDF]
Astronomy & Astrophysics, 2019 Context. Radio observations at metre-centimetre wavelengths shed light on the nature of the emission of H II regions. Usually this category of objects is dominated by thermal radiation produced by ionised hydrogen, namely protons and electrons.
M. Padovani +4 more
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