Related papers: OH 12.8-0.9: A New Water-Fountain Source
We present Very Large Array observations at 1.3 cm of several water maser detections obtained by previous single-dish studies of Bok globules in the Clemens & Barvainis (1988; CB) catalog. We report water maser emission in CB 3 (CB3-mm), CB…
The southern maser site OH 300.969+1.147 has been studied using the Long Baseline Array of the Australia Telescope National Facility. The 1665- and 1667-MHz hydroxyl ground-state transitions were observed simultaneously. A series of maps…
We present VLA 1.3 cm radio continuum and water maser observations as well as SMA SO$_2$ (226.300 GHz) and 1.3 mm dust continuum observations toward the massive star formation region IRAS 16547-4247. We find evidence of multiple sources in…
We report a trigonometric parallax measurement with the Very Long Baseline Array for the water maser in the distant high-mass star-forming region G75.30+1.32. This source has a heliocentric distance of 9.25+-0.45 kpc, which places it in the…
We present the results from long-term simultaneous monitoring observations of SiO and H2O masers toward the Mira variable star WX Serpentis. This study has been conducted with 21m single-dish radio telescopes of the Korean VLBI Network from…
We intended to study the incidence and characteristics of water masers in the envelopes of stars in the post-AGB and PN evolutionary stages. We have used the 64-m antenna in Parkes (Australia) to search for water maser emission at 22 GHz,…
We present the spectral and spatial evolution of H$_2$O masers associated with the water fountain source IRAS 18043$-$2116 found in the observations with the Nobeyama 45 m telescope and the Australia Telescope Compact Array. We have found…
We present the first circular polarization measurements of circumstellar H2O masers. Previously the magnetic field in circumstellar envelopes has been estimated using polarization observations of SiO and OH masers. SiO masers are probes of…
Water fountain stars represent a stage between the asymptotic giant branch (AGB) and planetary nebulae phases, when the mass loss changes from spherical to bipolar. These types of evolved objects are characterized by high-velocity jets in…
We present VLBI observations of the H$_2$O maser emission towards a selection of massive young stellar objects (YSOs). In one of these sources, IRAS20126+4104, the measured proper motions confirm that the water masers spots are tracing the…
Using the Green Bank Telescope, we conducted a ``snapshot'' survey for water maser emission toward the nuclei of 611 galaxies and detected eight new sources. The sample consisted of nearby (v < 5000 km/s) and luminous (M_B < -19.5)…
We wish to perform a statistical study of the location and motion of individual 22 GHz water maser cloudlets, characterized by sizes that are within a few au, with respect to the radio thermal emission from young stellar objects (YSO). For…
Astrophysical masers are widely used in star formation studies. In particular, they are valuable in investigations of high-mass star-forming regions that are difficult to observe at optical frequencies. We used multi-transition data to…
We use unpublished and published VLBI results to investigate the geometry and the statistical properties of the velocity field traced by H2O masers in five galactic regions of star formation -- Sgr B2(M), W49N, W51(MAIN), W51N, and W3(OH).…
We present a comparative multi-wavelength analysis of water maser-emitting regions and non-maser-emitting luminous 24 micron star-forming regions in the Andromeda Galaxy (M31) to identify the sites most likely to produce luminous water…
We have mapped the water maser emission associated with the infrared centers IRS1 and IRS3 of the NGC 2071IR star forming region at four epochs over ~4 months with the Very Long Baseline Array (VLBA). We detected 269 maser features with ~1…
Water vapor maser emission in the 6_{16}-5_{23} transition towards the narrow-line Seyfert 1 (NLS1) galaxy NGC 4051 has been discovered during an ongoing single-dish extragalactic water maser survey. The Doppler-shifted maser components…
H2O (22 GHz) and SiO masers (43, 86, 129 GHz) in the bipolar proto-planetary nebula OH231.8+4.2 were simultaneously monitored using the 21-m antennas of the Korean VLBI Network in 2009-2015. Both species exhibit periodic flux variations…
Galactic nuclei are well known sources of OH and H2O maser emission. It appears that intense star formation in ultra-luminous infrared galaxies drives most OH sources. In contrast, nuclear activity appears to drive most H2O sources. When…
We have investigated the stellar and interstellar content of the distant star formation region IRAS 17591-2228 (WISE HII region GAL 007.47+0.06). It is associated to a water maser, whose parallax distance is d=20.4^{+2.8} {-2.2} kpc,…