Results 11 to 20 of about 3,875,215 (299)
Diffuse continuum transfer in H���ii regions [PDF]
Monthly Notices of the Royal Astronomical Society, 2009 12 pages, 7 figures, to be published in ...
Williams, R. J. R., Henney, W. J.
openaire +3 more sources
A search for hypercompact HII regions in the Galactic Plane [PDF]
, 2018 22 pages, 8 figures, 6 tables, accepted by MNRASWe have carried out the largest and most unbiased search for hypercompact (HC) H II regions. Our method combines four interferometric radio continuum surveys (THOR, CORNISH, MAGPIS, and White2005) with far ...
A Y Yang +56 more
core +3 more sources
H II Region Driven Galactic Bubbles And Their Relationship To The Galactic Magnetic Field [PDF]
, 2012 The relative alignments of mid-infrared traced Galactic bubbles are compared to the orientation of the mean Galactic magnetic field in the disk. The orientations of bubbles in the northern Galactic plane were measured and are consistent with random ...
Clemens, D. P., Pavel, Michael D.
core +2 more sources
Quasar H II Regions During Cosmic Reionization [PDF]
, 2007 Cosmic reionization progresses as HII regions form around sources of ionizing radiation. Their average size grows continuously until they percolate and complete reionization.
Abel, Tom, Alvarez, Marcelo A.
core +5 more sources
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
core +2 more sources
Chlorine and Sulfur in Nearby Planetary Nebulae and H II Regions [PDF]
, 2011 We derive the chlorine abundances in a sample of nearby planetary nebulae (PNe) and H II regions that have some of the best available spectra. We use a nearly homogeneous procedure to derive the abundance in each object and find that the Cl/H abundance ...
Gloria Delgado-Inglada +4 more
core +1 more source
Ionization Front Instabilities in Primordial H II Regions [PDF]
, 2007 Radiative cooling by metals in shocked gas mediates the formation of ionization front instabilities in the galaxy today that are responsible for a variety of phenomena in the interstellar medium, from the morphologies of nebulae to triggered star ...
Norman, Michael L., Whalen, Daniel
core +1 more source
Properties of H II region populations in galaxies. II - The H II region luminosity function
The Astrophysical Journal, 1989 H-alpha emission-line fluxes have been measured for all of the detected H II regions in 30 nearby spiral and irregular galaxies, and these data are used to study the behavior of the H II region luminosity functions (LFs). In most galaxies, the LF is well represented by a power law function.
Robert C., Jr. Kennicutt +2 more
openaire +1 more source
Sagittarius B1: A Patchwork of H ii Regions and Photodissociation Regions [PDF]
The Astrophysical Journal, 2021 Abstract Sgr B1 is a luminous H ii region in the Galactic center immediately next to the massive star-forming giant molecular cloud Sgr B2 and apparently connected to it from their similar radial velocities. In 2018 we showed from SOFIA FIFI-LS observations of the [O iii] 52 and 88 μm lines that there is no central exciting star cluster ...
Janet P. Simpson +4 more
openaire +2 more sources
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