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Related papers: Studies of methanol maser rings

200 papers

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…

Astrophysics of Galaxies · Physics 2020-01-08 Sonu Tabitha Paulson , Jagadheep D. Pandian

Class I methanol masers are collisionally pumped and are generally correlated with outflows in star forming sites in the Galaxy. Using the VLA in its A-array configuration, we present a spectral line survey to identify methanol…

Astrophysics of Galaxies · Physics 2016-12-14 W. Cotton , F. Yusef-Zadeh

Methanol masers at 6.7 GHz have been found exclusively towards high-mass star forming regions. Recently, some Class 0 protostars have been found to display conditions similar to what are found in hot cores that are associated with massive…

Astrophysics · Physics 2009-11-13 J. D. Pandian , S. Leurini , K. M. Menten , A. Belloche , P. F. Goldsmith

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…

Astrophysics of Galaxies · Physics 2019-01-16 Matthew Rickert , F. Yusef-Zadeh , J. Ott

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…

Solar and Stellar Astrophysics · Physics 2022-12-07 Esraa Khafagy , khaled A. Edris , Osama M. Shalabiea , Anna Bartkiewicz , Anita M. S. Richards , Zainab Awad

Theoretical simulations and observations at different angular resolutions have shown that magnetic fields have a central role in massive star formation. Like in low-mass star formation, the magnetic field in massive young stellar objects…

Solar and Stellar Astrophysics · Physics 2015-06-17 G. Surcis , W. H. T. Vlemmings , H. J. van Langevelde , B. Hutawarakorn Kramer , A. Bartkiewicz , M. G. Blasi

A ring of dense molecular gas extending 2-7 pc orbits the supermassive black hole Sgr A* at the center of our Galaxy. Using the Green Bank Telescope, we detected water maser lines and both narrow (0.35 km/s) and broad (30 - 50 km/s)…

Astrophysics · Physics 2009-11-13 F. Yusef-Zadeh , J. Braatz , M. Wardle , D. Roberts

G339.88-1.26 is considered to be a good candidate for a massive star with a circumstellar disk. This has been supported by the observations of linearly distributed methanol maser spots believed to delineate this disk, and mid-infrared…

We have used the Australia Telescope Compact Array (ATCA) to undertake the first high angular resolution observations of 37.7-GHz ($7_{-2} - 8_{-1}E$) methanol masers towards a sample of eleven high-mass star formation regions which host…

Astrophysics of Galaxies · Physics 2018-08-15 Simon Ellingsen , Maxim Voronkov , Shari Breen , Jim Caswell , Andrej Sobolev

Context. Class II methanol masers at 6.7 and 12.2 GHz occur close to high-mass young stellar objects (HMYSOs). When they are observed simultaneously, such studies may contribute to refining the characterisation of local physical conditions.…

Astrophysics of Galaxies · Physics 2021-04-28 M. Durjasz , M. Szymczak , P. Wolak , A. Bartkiewicz

The GLIMPSE and MSX surveys have been used to examine the mid-infrared properties of a statistically complete sample of 6.7 GHz methanol masers. The GLIMPSE point sources associated with methanol masers are clearly distinguished from the…

Astrophysics · Physics 2009-11-13 S. P. Ellingsen

Very long baseline interferometry (VLBI) monitoring of the 6.7 GHz methanol maser allows us to measure the internal proper motions of the maser spots and therefore study the gas motion around high-mass young stellar objects. To this end, we…

The European VLBI Network (EVN) has been used to make phase referenced, wide-field (several arcminute) spectral line observations of the 6.7-GHz methanol maser emission towards W51. In the W51main region, the bulk of the methanol is offset…

Astrophysics · Physics 2009-11-10 C. J. Phillips , H. J. van Langevelde

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…

Astrophysics of Galaxies · Physics 2014-06-04 L. Olmi , E. D. Araya , P. Hofner , S. Molinari , J. Morales Ortiz , L. Moscadelli , M. Pestalozzi

A southern hemisphere survey of methanol emission sources in two millimeter wave transitions has been carried out using the ATNF Mopra millimetre telescope. Sixteen emission sources have been detected in the 3(1)-4(0)A+ transition of…

Astrophysics · Physics 2009-10-31 I. E. Valtts , S. P. Ellingsen , V. I. Slysh , S. V. Kalenskii , R. Otrupcek , M. A. Voronkov

We have used the Australia Telescope National Facility Mopra 22m millimetre telescope to search for emission from the 85.5-GHz and 86.6-GHz transitions of methanol. The search was targeted towards 22 star formation regions which exhibit…

Astrophysics · Physics 2009-11-07 S. P. Ellingsen , D. M. Cragg , V. Minier , E. Muller , P. D. Godfrey

In the early days of methanol maser discoveries the 9(2)-10(1) A+ transition at 23.1 GHz was found to exhibit maser characteristics in the northern star-forming region W3(OH), and probable maser emission in two other sources. Attention…

Astrophysics · Physics 2009-11-10 D. M. Cragg , A. M. Sobolev , J. L. Caswell , S. P. Ellingsen , P. D. Godfrey

We present accurate absolute astrometry of 6.7 GHz methanol masers detected in the Arecibo Methanol Maser Galactic Plane Survey using MERLIN and the Expanded Very Large Array (EVLA). We estimate the absolute astrometry to be accurate to…

Solar and Stellar Astrophysics · Physics 2015-05-27 J. D. Pandian , E. Momjian , Y. Xu , K. M. Menten , P. F. Goldsmith

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,…

Astrophysics · Physics 2007-05-23 S. V. Kalenskii , V. I. Slysh , I. E. Val'tts

The 6.7 GHz maser transition of methanol has been found exclusively towards massive star forming regions. A majority of the masers have been found to lack the presence of any associated radio continuum. This could be due to the maser…

Astrophysics of Galaxies · Physics 2015-05-19 J. D. Pandian , E. Momjian , Y. Xu , K. M. Menten , P. F. Goldsmith