Results 1 to 10 of about 42 (35)
Water vapor and silicon monoxide maser observations in the protoplanetary nebula OH 231.8+4.2 [PDF]
Astronomy and Astrophysics, 2007 Context. OH 231.8+4.2 is a well studied preplanetary nebula (pPN) around a binary stellar system that shows a remarkable bipolar outflow. Aims. To study the structure and kinematics of the inner 10-80AU nebular regions probed by SiO and H 2 O maser emission, where the agents of wind collimation are expected to operate, in order to gain insights into ...
Valentin Bujarrabal +2 more
exaly +4 more sources
Astronomical Journal, 1978 Seven Mira variable stars with silicon monoxide maser emission have been found. All are later than M4 and heavily reddened. Two were observed near maximum light. One, Y Cas, seems to bear out the correlation of 43-GHz SiO maser luminosity and mean spectral type at maximum light. RT Aql, however, falls about 1 mag below the expected brightness.
D F Dickinson, L W Brown
exaly +2 more sources
Is there a maser in the silicon monoxide ground state
Astrophysical Journal, 1975 Observations are reported of weak emission from the ground vibrational state of SiO in the Orion molecular cloud. It is shown that this emission has a rather smooth low-intensity profile extending over a large velocity range and is present at velocities where maser emissions from the first and second vibrational states are absent.
L E Snyder, F J Lovas, D Buhl
exaly +2 more sources
Silicon Monoxide: Detection of Maser Emission from the Second Vibrationally Excited State
Astrophysical Journal, 1974 Frank J. Lovas
exaly +2 more sources
Polarized Maser Emission with In-source Faraday Rotation
The Astrophysical Journal, 2023 We discuss studies of polarization in astrophysical masers with particular emphasis on the case where the Zeeman splitting is small compared to the Doppler profile, resulting in a blend of the transitions between magnetic substates.
T. L. Tobin, M. D. Gray, A. J. Kemball
doaj +1 more source
An Updated Reference Frame for the Galactic Inner Parsec
The Astrophysical Journal, 2023 Infrared observations of stellar orbits about Sgr A* probe the mass distribution in the inner parsec of the Galaxy and provide definitive evidence for the existence of a massive black hole.
Jeremy Darling +5 more
doaj +1 more source
The Spatial Structure of Silicon Monoxide Masers [PDF]
Symposium - International Astronomical Union, 1984 VLBI observations of stellar masers provide important constraints on models for maser excitation and for the dynamics and physical conditions in circumstellar envelopes. The spatial distribution and apparent sizes of Si0 masers toward several late type variable stars and toward the star-forming region in Orion have been measured using the 75 km ...
openaire +1 more source
The Astrophysical JournalStudying stars that are located off the Galactic plane is important for understanding the formation history of the Milky Way. We searched for SiO masers toward off-plane O-rich asymptotic giant branch (AGB) stars from the catalog presented by Mauron et ...
Wenjin Yang +9 more
doaj +1 more source
Investigating Asymmetry Development from SiO to H2O Maser Regions in VX Sagittarii
The Astronomical JournalSimultaneous very-long-baseline interferometry monitoring observations of H _2 O and SiO masers toward VX Sagittarii were conducted from 2014 February to 2019 January.
Dong-Hwan Yoon +4 more
doaj +1 more source