Related papers: Testing the Evolutionary Sequence of High Mass Pro…
We have observed the massive star forming region associated with the early B protostar G192.16-3.84 in NH3(1,1), 22.2 GHz water masers, 1.3 cm continuum emission, and at 850 microns. The dense gas associated with G192.16 is clumpy,…
Context: NGC7538 is known to host a 6.7 and 12.2GHz methanol maser cospatial with a Ultra Compact (UC) HII region, IRS1. Aims: We report on the serendipitous discovery of two additional 6.7GHz methanol masers in the same region, not…
We investigate the nuclear environment of galaxies with observed 22 GHz water megamaser in their subparsec edge-on accretion disks, using 33 GHz (9mm) radio continuum data from VLA, with a resolution of ~ 0.2-0.5 arcsecs, and relate the…
The high-mass star-forming site G009.62+00.20E hosts the 6.7 GHz methanol maser source with the greatest flux density in the Galaxy which has been flaring periodically over the last ten years. We performed high-resolution astrometric…
We present the first EVN maps of 6.7 GHz methanol masers of three high-mass protostar candidates selected from the Torun unbiased survey of the Galactic plane. A variety of linear and arc like structures was detected. A number of maser…
We present detections of the absorption band at 3.53 micron due to solid methanol toward three low-mass young stellar objects located in the Serpens and Chameleon molecular cloud complexes. The sources were observed as part of a large…
We investigate gas contents of star-forming galaxies associated with protocluster 4C23.56 at z = 2.49 by using the redshifted CO(3-2) and 1.1 mm dust continuum with the Atacama Large Millimeter/submillimeter Array. The observations unveil…
We present 247-GHz molecular line observations of methanol (CH$_3$OH) toward sixteen massive star-forming regions, using the APEX telescope with an angular resolution of $25''$. The sample covers a range of evolutionary states, including…
We have compared the occurrence of 6.7-GHz and 12.2-GHz methanol masers with 22-GHz water masers and 6035-MHz excited-state OH masers in the 100 square degree region of the southern Galactic plane common to the Methanol Multibeam (MMB) and…
We report a simultaneous 44 and 95 GHz class I methanol maser survey toward 144 sources from the 95 GHz class I methanol maser catalog. The observations were made with the three telescopes of the Korean very long baseline interferometry…
We present 1.05 mm ALMA observations of the deeply embedded high-mass protocluster G11.92-0.61, designed to search for low-mass cores within the accretion reservoir of the massive protostars. Our ALMA mosaic, which covers an extent of ~0.7…
We have used the Australia Telescope Compact Array (ATCA) to make the first high resolution observations of a large sample of class~I methanol masers in the 95-GHz ($8_0$--$7_1$A$^+$) transition. The target sources consist of a…
Results of a survey of Galactic star-forming regions in the lines of methanol 8_{-1}-7_0E at 229.8 GHz, 3_{-2}-4_{-1}E at 230.0 GHz, 0_0-1_{-1}E at 108.9 GHz, and a series of methanol lines J_1-J_0E near 165 GHz are presented. Two masers,…
We present sensitive high angular resolution ($\sim$ 1$"$) millimeter continuum and line observations from the massive star forming region DR21(OH) located in the Cygnus X molecular cloud. Within the well-known dusty MM1-2 molecular cores,…
Results of the long-term monitoring observations of the 6.7 GHz Class II methanol masers associated with the four high-mass star-forming regions by Hitachi 32-m radio telescope are presented. We detected periodic flux variability in…
We have observed 13 methanol maser sources associated with massive star-forming regions; W3(OH), Mon R2, S 255, W 33A, IRAS 18151-1208, G 24.78+0.08, G 29.95-0.02, IRAS 18556+0136, W 48, OH 43.8-0.1, ON 1, Cep A and NGC 7538 at 6.7 GHz…
High mass stars play an important role in the Interstellar Medium, but much remains to be known about their formation. Class I methanol masers may be unique tracers of an early stage of high mass star formation, and a better understanding…
The Central Molecular Zone (CMZ) spans the inner ~450 pc (3 degrees) of our Galaxy. This region is defined by its enhanced molecular emission and contains 5% of the entire Galaxy's molecular gas mass. However, the number of detected star…
We report on EVN imaging of the 6.7 GHz methanol maser emission from the candidate high-mass protostar G23.657-0.127. The masers originate in a nearly circular ring of 127 mas radius and 12 mas width. The ring structure points at a central…
We present high-frequency (18-24 GHz) radio continuum observations towards 335 methanol masers, excellent signposts for young, embedded high-mass protostars. These complete the search for hypercompact HII (HCHII) regions towards young…