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Full-Text Articles in Physics
On The Theory Of Astronomical Masers In Three Dimensions, Moshe Elitzur
On The Theory Of Astronomical Masers In Three Dimensions, Moshe Elitzur
Physics and Astronomy Faculty Publications
In the standard theory of three-dimensional astronomical masers, the radiation field is described as if the source were comprised of a collection of linear masers. To leading order, the standard theory is shown to provide the correct description of three-dimensional masers and its results remain intact, but only within a frequency core whose half-width is χsΔνD, where ΔνD is the Doppler width and χs is a dimensionless parameter. For any given geometry, χs is ~1θsat, where θsat is the beaming angle of a maser with that geometry that has …
Planar H2O Masers In Star-Forming Regions, Moshe Elitzur, David J. Hollenbach, Christopher F. Mckee
Planar H2O Masers In Star-Forming Regions, Moshe Elitzur, David J. Hollenbach, Christopher F. Mckee
Physics and Astronomy Faculty Publications
The planar geometry of shocked material is the key property in enabling the high brightness temperatures of H20 masars in star-forming regions. We solve for the brightness temperature, the beaming angle, and the maser spot size for thin, saturated planar masers under the assumption that the velocity change across the maser due to ordered motions is small compared with the thermal or microturbulent line width. For a given set of physical parameters, the brightness temperature is essentially fully determined by the length of the velocity-coherent region in the shocked plane along the line of sight. The geometry in the transverse …