ionization front

ionization front

See Strömgren sphere.

ionization front

[‚ī·ə·nə′zā·shən ‚frənt]
(astronomy)
A transition region that separates interstellar gas in which a given atomic species (usually hydrogen) is mostly ionized from interstellar gas in which it is mostly neutral.
References in periodicals archive ?
The ionization front known as the "Bright Bar" is the strikingly straight edge running from the northeast to the southwest border of the Huygens region.
This cool observation technique also helps convince me the orangepink color is real, because I saw color along the outer edge of the Bright Bar ionization front and in the small patch just southwest of the Trapezium in the shrouded star-forming area, Orion S, exactly where color exists.
The main ionizing source of this cluster is named [[theta].sup.1] Ori C (O7V [2]), which is responsible of the bulk of the nebular emission from the main ionization front (MIF).
These models combine simulations of radiative transfer, hydrodynamics, and atomic physics to predict fundamental parameters like the density, temperature, and ionization structure of the photoevaporation flows through the proplyd ionization front (see Figure 5 [65, 69]).
The Sandia concept, called the Ionization Front Accelerator (IFA), does not suffer this disadvantage.
To accelerate the electron-beam front, the physicists provide an accelerated, moving ionization front in the cesium.
The famous Pelican Nebula, IC 5070, is an ionization front illuminated by young, energetic stars within a vast molecular cloud in Cygnus.
Within the next 20,000 years or so, the advancing ionization front will overrun the nearby newly forming star, slowing or stopping its growth by destroying the materials it needs to continue coalescing.
Wen's calculations reveal that the Orion Nebula is a very thin emitting layer lying on top of a highly irregular ionization front. The front is formed where all of the high-energy photons from [Theta.sup.1] C are eating their way into the molecular gas and ionizing it.
Ionization fronts powered by massive stars embedded in the NGC 2467 complex are plowing through the region's gas and dust, compressing it and triggering ongoing star birth.
A less violent possibility involves compression of the nebular material by ionization fronts from the intensely hot, spectral-type 09V star 10 Lacertae, 410 light-years from LBN 534.