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Related papers: Maser action in methanol transitions

200 papers

We present the unambiguous discovery of six new class II methanol maser transitions, three of which are torsionally excited (vt=1). The newly discovered 6.18-GHz 17_-2 -> 18_-3 E (vt=1), 7.68-GHz 12_4 -> 13_3 A- (vt=0), 7.83-GHz 12_4 ->…

Astrophysics of Galaxies · Physics 2019-05-15 S. L. Breen , A. M. Sobolev , J. F. Kaczmarek , S. P. Ellingsen , T. P. McCarthy , M. A. Voronkov

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

We characterize the molecular environment of candidate massive young stellar objects (MYSOs) signposted by methanol masers. Single pixel observations of 10 transitions of HCO^+, CO and CS isotopomers were carried out, using the IRAM 30m…

Astrophysics · Physics 2009-11-13 M. Szymczak , A. Bartkiewicz , A. M. S. Richards

We present Very Large Array observations of the 7_0-6_1 A^+ methanol maser transition at 44 GHz towards NGC 6334F, G8.67-0.36, and M17. These arcsecond resolution observations complete a previous, larger VLA survey of this maser transition…

Astrophysics of Galaxies · Physics 2015-05-20 Laura Gomez , Leticia Luis , Idalia Hernandez-Curiel , Stan Kurtz , Peter Hofner , Esteban Araya

The aim of this study is to investigate the distribution and excitation of the methanol gas around Cep A and to describe the physical conditions of the region. In addition the large scale abundance distribution is determined in order to…

The ATCA, MERLIN and VLA interferometers were used to measure the absolute positions of 35 6.7 GHz methanol masers to subarcsecond or higher accuracy. Our measurements represent essential preparatory data for Very Long Baseline…

Astrophysics of Galaxies · Physics 2015-05-14 Y. Xu , M. A. Voronkov , J. D. Pandian , J. J. Li , A. M. Sobolev , A. Brunthaler , B. Ritter , K. M. Menten

We present the most complete to date interferometric study of the centimeter wavelength methanol masers detected in G358.93-0.03 at the burst and post-burst epochs. A unique, NIR/(sub)mm-dark and FIR-loud MYSO accretion burst was recently…

We present a catalogue of 12.2-GHz methanol masers detected towards 6.7-GHz methanol masers observed in the unbiased Methanol Multibeam (MMB) survey in the longitude range 330\circ (through 360\circ) to 10\circ. This is the first portion of…

Astrophysics of Galaxies · Physics 2015-06-03 Shari Breen , Simon Ellingsen , James Caswell , James Green , Maxim Voronkov , Gary Fuller , Lyshia Quinn , Adam Avison

We report the first observations in a rare family of class II methanol maser transitions in both CH$_3$OH and $^{13}$CH$_3$OH toward three southern high-mass star formation regions, along with the first maser detected in the $^{13}$CH$_3$OH…

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…

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''…

Astrophysics · Physics 2008-12-18 A. Bartkiewicz , A. Brunthaler , M. Szymczak , H. J. van Langevelde , M. J. Reid

Methanol masers are often found in linear distributions, and it has been hypothesized that these masers are tracing circumstellar accretion disks around young massive stars. However, recent observations in H2 emission have shown what appear…

Astrophysics · Physics 2009-11-13 J. M. De Buizer , R. O. Redman , S. N. Longmore , J. Caswell , P. A. Feldman

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…

Solar and Stellar Astrophysics · Physics 2020-05-20 Wenjin Yang , Ye Xu , Yoon Kyung Choi , Simon P. Ellingsen , Andrej M. Sobolev , Xi Chen , Jingjing Li , Dengrong Lu

We present (sub)millimeter imaging at 0.5'' resolution of the massive star-forming region G358.93-0.03 acquired in multiple epochs at 2 and 3 months following the recent flaring of its 6.7 GHz methanol maser emission. Using SMA and ALMA, we…

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…

Astrophysics · Physics 2008-11-26 Y. Xu , Z. -Q. Shen , J. Yang , X. W. Zheng , A. Miyazaki , K. Sunada , H. J. Ma , J. J. Li , J. X. Sun , C. C. Pei

Context: Methanol masers of Class I (collisionally-pumped) and Class II (radiatively-pumped) have been studied in great detail in our Galaxy in a variety of astrophysical environments such as shocks and star-forming regions and are helpful…

We present the results of the further investigation of the Class II methanol maser emission in the $14_1 - 14_0$ A$^{-+}$ transition at 349.1 GHz discovered in 2016 in the remarkable core S255IR-SMA1, harboring a $\sim$20 M$_\odot$…

Astrophysics of Galaxies · Physics 2025-08-01 I. I. Zinchenko , S. V. Salii , A. M. Sobolev , I. A. Zaichikova , S. -Y. Liu , Y. -N. Su

The Australia Telescope Compact Array (ATCA) participated in a number of survey programs to search for and image common class I methanol masers (at 36 and 44 GHz) with high angular resolution. In this paper, we discuss spatial and velocity…

Astrophysics of Galaxies · Physics 2018-08-22 M. A. Voronkov , S. L. Breen , S. P. Ellingsen , C. H. Jordan

We present observations of massive star-forming regions selected from the IRAS Point Source Catalog. The observations were made with the Very Large Array and the Large Millimeter Telescope to search for Class I methanol masers. We made…

We report accurate laboratory measurements of selected methanol transition frequencies between 0.834 and 230 GHz in order to facilitate astronomical velocity analyses. New data have been obtained between 10 and 27 GHz and between 60 and 119…

Astrophysics · Physics 2011-03-02 H. S. P. Mueller , K. M. Menten , H. Maeder
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