Related papers: Ground-State SiO Maser Emission Toward Evolved Sta…
We used the Submillimeter Array to image the SiO maser emission in the $v=1$, \$J=5-4$ transition associated with the peculiar red supergiant VY Canis Majoris. We identified seven maser components and measured their relative positions and…
We present the results of the first high angular resolution observations of SiO maser emission towards the star forming region W51-IRS2 made with the Very Large Array (VLA) and Very Long Baseline Array (VLBA). Our images of the water maser…
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 present high spatial resolution observations of ground-state OH masers achieved with the Australia Telescope Compact Array (ATCA). These observations targeted 253 pointing centres containing OH maser candidates at all four ground-state…
We performed interferometric observations of a high-mass protostellar candidate IRAS 18566+0408 in the \nh3 (J,K)=(1,1), (2,2) and (3,3) inversion transitions, the SiO J=2-1 and HCN J=1-0 lines, and the 43 and 87 GHz continuum emission…
We present results of spectral line observations of the ground state transitions of hydroxyl(OH) toward supernova remnant IC 443 carried out with the Green Bank Telescope. At a spatial resolution of 7.2 arcminutes we detect weak, extended…
Both magnetic fields and photospheric/atmospheric dynamics can be involved in triggering the important mass loss observed in evolved cool stars. Previous works have revealed that these objects exhibit a magnetic field extending beyond their…
We present milliarsecond-resolution maps of the SiO maser emission $v$=1 J=2--1 (3 mm) in the bipolar post-AGB nebula OH 231.8+4.2, and compare them with our previous observations of the $v$=2 J=1--0 line (7 mm). Our observations show that…
We have conducted multi-epoch EVN observations of the 22.2 GHz water masers towards four high-mass star forming regions (Sh 2-255 IR, IRAS 23139+5939, WB89-234, and OMC2). The (three) observing epochs span a time range of 6 months. In each…
The CO(1--0) and [\ion{C}{1}](1--0) emission lines are well-established tracers of cold molecular gas mass in local galaxies. At high redshift, where the interstellar medium (ISM) is likely to be denser, there have been limited direct…
We report the first Very Long Baseline Array (VLBA) observations of 43 GHz v=1, J=1-0 SiO masers in the circumstellar envelope of the M-type semi-regular supergiant variable star AH Sco at 2 epochs separated by 12 days in March 2004. These…
We performed a survey in the SiO $J=5\rightarrow4$ line toward a sample of 199 Galactic massive star-forming regions at different evolutionary stages with the SMT 10 m and CSO 10.4 m telescopes. The sample consists of 44 infrared dark…
The star-forming region W75N hosts bright OH masers that are observed to be variable. We present observations taken in 2008 of the ground-state OH maser transitions with the Very Long Baseline Array (VLBA) and the Multi-Element Radio-Linked…
We present observations towards a high-mass ($\rm >40\,M_{\odot}$), low luminosity ($\rm <10\,L_{\odot}$) $\rm 70\,\mu$m dark molecular core G 28.34 S-A at 3.4 mm, using the IRAM 30 m telescope and the NOEMA interferometer. We report the…
We conducted an SiO maser survey towards 221 O-rich AGB stars with the aim of identifying maser emission associated with the Sagittarius stellar stream. In this survey, maser emission was detected in 44 targets, of which 35 were new…
We performed the first VLBI observations of the SiO v=1 and v=2 J=1--0 masers in a Proto Planetary Nebula OH 231.8+4.2 (also known as the Rotten Egg nebula), at milliarcsecond resolution. Only the v=2 maser transition was detected. We…
A stellar hydrodynamic pulsation model has been combined with a SiO maser model in an attempt to calculate the temporal variability of SiO maser emission in the circumstellar envelope (CE) of a model AGB star. This study investigates…
Using the 3.6/4.5/5.8/8.0 micron images with 1.2 arcsec pixel resolution from the Spitzer/GLIMPSE survey, we investigated 23 masing and 18 very red objects that were not identified in the 2MASS survey. Counterparts for all selected objects…
A group of Mira variables in the solar neighborhood show unusual spatial motion in the Galaxy. To study this motion in a much larger scale in the Galaxy, we newly surveyed 134 evolved stars off the Galactic plane by SiO maser lines,…
We report on the multi-epoch observations of H2O maser emission in star forming region OH 43.8-0.1 carried out with VLBI Exploration of Radio Astrometry (VERA). The large-scale maser distributions obtained by single-beam VLBI mapping reveal…