Results 171 to 180 of about 4,740 (197)
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2004
A review on strong masers and their assocn. with star formation, recent VLBI measurements of the structure and dynamics of methanol masers, the masers in the envelopes of evolved stars, and extragalactic masers. [on SciFinder (R)]
Booth, R. S., Diamond, P. J.
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A review on strong masers and their assocn. with star formation, recent VLBI measurements of the structure and dynamics of methanol masers, the masers in the envelopes of evolved stars, and extragalactic masers. [on SciFinder (R)]
Booth, R. S., Diamond, P. J.
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Radiative instabilities in astrophysical masers
1993We have previously found that the solutions to the equations of radiative transfer for astrophysical masers are unstable. Here, we provide additional information on the behavior of the interior of the masing region during the variations that result from the instability.
Gerardo A. Scappaticci +1 more
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Wide spectrum H2O sources—astrophysical Raman masers
Pramana, 1975The extraordinarily wide 22 GHz emission from W49A and two other galactic HII regions is discussed, and arguments presented why the entire width of these spectra cannot be attributed to the 616 → 523 transition of H2O. It is suggested that most of the weak emission with large frequency shifts is due to stimulated Raman scattering of the strong central ...
V Radhakrishnan +2 more
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Statistical nature of astrophysical maser radiation for linear masers
Canadian Journal of Physics, 1992The validity of the assumption of Gaussian statistics, a basis for the validity of use of the radiative transfer equation and for a lot of current astrophysical maser theories, is investigated. For tractability the investigation in this paper is confined to astrophysical linear masers, which are very important to astrophysical maser theories.
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Polarization Properties of Astrophysical Masers
1973Observed interstellar OH and H2O maser lines at 18 cm and 1.35 cm exhibit unusual polarization properties. The OH emitters with the highest brightness temperatures, usually associated with H II regions, almost always show a high degree of circular polarization. The H2O maser line, on the other hand, is rarely polarized, and then only linearly polarized.
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Plasma-maser effects in plasma astrophysics
Space Science Reviews, 1986The role of a new mode coupling effect (plasma-maser) in space plasma physics is reviewed. The new maser effect, the idea that the resonant electrons with the low-frequency mode can amplify the high-frequency mode, does not require population inversion of electrons. The generation mechanisms of ULF modulated ELF emissions, auroral kilometric radiation,
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An electron cyclotron maser instability for astrophysical plasmas
The Physics of Fluids, 1983The electron cyclotron maser instability is analyzed for a plasma which consists of a suprathermal electron component characterized by velocity-space anisotropies in directions both parallel and perpendicular to the ambient magnetic field, as well as a high-density thermal plasma in which ωe∼Ωe (where ωe and Ωe are the electron plasma and cyclotron ...
Freund, H. P. +3 more
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Laboratory experiment to investigate astrophysical cyclotron-maser emission
2011 International Conference on Infrared, Millimeter, and Terahertz Waves, 2011Experiments and simulations are reported that study the processes by which planetary and stellar auroral cyclotron-maser emission occurs.
D. C. Speirs +4 more
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Cosmic MASERS - A Powerful Tool For Astrophysics
1996Abstract Cosmic masers were discovered accidentally in 1965 by radio astronomers who were trying to map the distribution of gas in molecular clouds by measuring the absorption due to OH molecules against thermal background sources [Weaver et al., 1965, Gundermann, 1965].
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3D Models of Astrophysical Masers with Polarization
Proceedings of 15th European VLBI Network Mini-Symposium and Users' Meeting — PoS(EVN2022), 2023Malcolm Gray +5 more
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