相关论文: Massive Star Formation in the Molecular Ring Orbit…
We present a multiwavelength study of five methanol maser sites which are not directly associated with a strong ($>100$ mJy) radio continuum source: G 31.28+0.06, G 59.78+0.06, G 173.49+2.42 (S231, S233IR), G 188.95+0.89 (S252, AFGL5180)…
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…
OH(1720 MHz) and methanol masers are now recognized to be excellent probes of the interactions of supernova remnants with molecular clouds and tracers of massive star formation, respectively. To better understand the nature of star…
It is often assumed that the strong gravitational field of a super-massive black hole disrupts an adjacent molecular cloud preventing classical star formation in the deep potential well of the black hole. Yet, young stars have been observed…
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…
Methanol masers are often detected in regions of intense star formation. Several studies in the last decade indicate that they may even be the earliest signpost of a high-mass star-forming region. Their powerful emission make them very good…
We present a study of molecular outflows using high-resolution mapping of the CO (1-0) line emission toward eight relatively nearby 6.7 GHz methanol masers, which are associated with massive star forming regions. Outflows were detected in…
We present the results of studies of a new class of 6.7 GHz methanol maser sources with a ring-like emission structure discovered recently with the EVN. We have used the VLA to search for water masers at 22 GHz and radio continuum at 8.4…
We present millimeter molecular-line complemented by optical observations, along with a reanalysis of archival centimeter HI and continuum data, to infer the global dynamics and determine where dense molecular gas and massive stars…
Methanol masers are associated with young high-mass stars and are an important tool for investigating the process of massive star formation. The recently discovered methanol maser ring in G23.657-00.127 provides an excellent ``laboratory''…
We report detection of moderate to high-mass star formation in an infrared dark cloud (G11.11-0.12) where we discovered class II methanol and water maser emissions at 6.7 GHz and 22.2 GHz, respectively. We also observed the object in…
We present an interferometric survey of the 44 GHz class I methanol maser transition toward a sample of 69 sources consisting of High Mass Protostellar Object candidates and Ultracompact (UC) H II regions. We found a 38% detection rate (16…
We present radio and infrared observations indicating on-going star formation activity inside the $\sim2-5$ pc circumnuclear ring at the Galactic center. Collectively these measurements suggest a continued disk-based mode of on-going star…
The presence of young massive stars orbiting on eccentric rings within a few tenths of a parsec of the supermassive black hole in the Galactic centre is challenging for theories of star formation. The high tidal shear from the black hole…
High-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'…
Methanol maser emission has proven to be an excellent signpost of regions undergoing massive star formation (MSF). To investigate their role as an evolutionary tracer, we have recently completed a large observing program with the ATCA to…
Methanol masers at 6.7 GHz are the brightest of class II methanol masers and have been found exclusively towards massive star forming regions. These masers can thus be used as a unique tool to probe the early phases of massive star…
Several thousand solar masses of molecular, atomic and ionized gas lie in the innermost ~10 pc of our Galaxy. The most relevant structure of molecular gas is the circumnuclear ring (CNR), a dense and clumpy ring surrounding the supermassive…
Maser lines from different molecular species, including water, hydroxyl, and methanol, are common observational phenomena associated with massive star forming regions. In particular, the methanol maser appears as an ideal tool to study the…
We introduce a study of the massive star forming region IRAS 18144--1723 using observations of the 6.7 GHz methanol maser line. Such regions are opaque at short wavelengths but can be observed through radio emission lines. In this study we…