Results 41 to 50 of about 154 (145)
Interstellar Scattering and the Sizes of Astronomical Masers
The Astrophysical Journal, 1972 The suggestion is explored that scattering by inhomogeneities in the distribution of electrons causes astronomical masers to appear larger than their actual sizes. It is shown that neither scattering near the source nor scattering in the intervening medium is sufficiently strong to produce this effect.
Robert W. Boyd, Michael W. Werner
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VLBI observations of interstellar ammonia masers
The Astrophysical Journal, 1991 The first VLBI measurement of interstellar ammonia masers is reported. The positions, as well as size and brightness temperature limits, for the masers in the NH 3 (9, 6) inversion transition that are associated with the ultracompact H II regions W51 e1 and e2 are obtained. The masers arise from two positions, each of which is located close to but not
Preethi Pratap +4 more
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CH3OH Thermal Lines Traces 6.7 GHz CH3OH Maser Variation of High-mass Protostar G353.273+0.641
The Astrophysical JournalThis study reports an analysis of the 6.7 GHz CH _3 OH maser in the high-mass protostar G353.273+0.641 (G353), utilizing data from the Tianma Radio Telescope.
Shi-Min Song +3 more
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First Detection of Circular Polarization in 4.7 GHz Excited OH Masers
The Astrophysical JournalWe report the first detection of circular polarization in 4.7 GHz excited OH masers in star-forming regions made using full Stokes measurements with the Green Bank 100 m telescope.
Derck P. Smits, Paul Fallon
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Asymptotic giant branch stars in the GLIMPSE database
Astronomy & AstrophysicsAims. The GLIMPSE database contains over one hundred million point sources between longitudes of −60° and +60° and most of these are asymptotic giant branch (AGB) stars within 16 kpc from the Sun.
Habing H. J., Habing M. A.
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Maser Activity of Organic Molecules toward Sgr B2(N)
The Astrophysical JournalAt centimeter wavelengths, single-dish observations have suggested that the Sagittarius (Sgr) B2 molecular cloud at the Galactic Center hosts weak maser emission from several organic molecules, including CH _2 NH, HNCNH, and HCOOCH _3 . However, the lack
Ci Xue +7 more
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Detections of Compact Radio Continuum toward Methanol Maser Rings Using the VLA
The Astrophysical JournalHigh-mass protostars are deeply embedded in dust inside their natal cores and are not easily detectable. However, maser emission at centimeter wavelengths, owing to its high brightness, enables us to study gas kinematics in protostars’ circumstellar ...
Anna Bartkiewicz +7 more
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Polarization Observations of a Sample of 6.7 GHz Methanol Masers
The Astrophysical JournalSpectra of 6.7 GHz methanol masers from 21 pointings of known star-forming regions are reported. C -band observations, using the Green Bank Telescope in full Stokes mode, have measured how polarization properties vary across the maser profiles in each ...
Paul Fallon, Derck P. Smits
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Polarization Observations of a Sample of Excited OH Masers
The Astrophysical JournalSpectra of 4.7 and 6.0 GHz excited OH masers from 21 pointings towards known star-forming regions are reported. The C -band observations, using the Green Bank Telescope in full Stokes mode, have measured how polarization properties vary across the maser ...
Derck P. Smits, Paul Fallon
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Water Maser Detections toward 70 μm Infrared Dark Clumps at Early Star Formation Stage
The Astrophysical Journal LettersWater masers provided powerful probes of shocked gas and protostellar activity during the early stages of star formation. Using Very Large Array K -band observations of the 22 GHz water line, we report the first detections of water masers toward dense ...
Chao Ou +4 more
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