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Related papers: Maser action in methanol transitions

200 papers

We have used the Australian Long Baseline Array (LBA) to produce milliarcsecond images of five sites of methanol maser emission at 6.7 GHz. These are all sites that have linear morphologies at arcsecond resolutions, which have been…

Astrophysics · Physics 2009-11-10 R. Dodson , R. Ojha , S. P. Ellingsen

We present the results of a 5-year monitoring program of 42 sources targeted at 6.7 GHz methanol masers, conducted from March 2017 to October 2022 using the Irbene 32 and 16 meter radio telescopes. Sources were observed with irregular…

Astrophysics of Galaxies · Physics 2023-10-13 A. Aberfelds , J. Šteinbergs , I. Shmeld , R. A. Burns

The role of magnetic fields during the protostellar phase of high-mass star-formation is a debated topic. In particular, it is still unclear how magnetic fields influence the formation and dynamic of disks and outflows. Most current…

Solar and Stellar Astrophysics · Physics 2015-05-14 G. Surcis , W. H. T. Vlemmings , R. Dodson , H. J. van Langevelde

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

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

We present the first 6.7 GHz methanol maser linear polarization map of the extended filamentary maser structure around the compact HII region W3(OH). The methanol masers show linear polarization up to 8 per cent and the polarization angles…

Astrophysics · Physics 2009-11-11 W. H. T. Vlemmings , L. Harvey-Smith , R. J. Cohen

We present the second portion of an unbiased survey of the Galactic plane for 6668-MHz methanol masers. This section of the survey spans the longitude range 6 degrees to 20 degrees. We report the detection of 119 maser sources, of which 42…

We have used the Australia Telescope Compact Array (ATCA) to make a sensitive search for maser emission from the 4765-MHz transition of OH towards a sample of 55 star formation regions. Maser emission with peak flux densities in excess of…

Astrophysics · Physics 2007-05-23 R. Dodson , S. Ellingsen

Recently, a comparison between the locations of 6.7-GHz methanol masers and dust continuum emission has renewed speculation that these masers can be associated with evolved stars. The implication of such a scenario would be profound,…

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…

Astrophysics of Galaxies · Physics 2024-02-28 Yoshihiro Tanabe , Yoshinori Yonekura

We present a study of signatures of on-going star formation in a sample of protostellar objects with enhanced 4.5 {\mu}m emission ('green' sources) near the Galactic center. To understand how star formation in the Galactic center region…

Astrophysics of Galaxies · Physics 2015-05-27 Edward T. Chambers , Farhad Yusef-Zadeh , Doug Roberts

An intensive monitoring program of 54 6.7-GHz methanol maser sources was carried out at the Hartebeesthoek Radio Astronomy Observatory from January 1999 to April 2003. The monitoring program was subsequently continued on 19 sources of…

Astrophysics · Physics 2009-11-13 Sharmila Goedhart , Michael J. Gaylard , D. Johan van der Walt

Aims.Molecular masers, including methanol and hydroxyl masers, and in particular the ones in excited rotational states (ex-OHmasers), are one of the most informative tools for studying star-forming regions. So, the discovery, of new maser…

Astrophysics of Galaxies · Physics 2021-08-04 O. Patoka , O. Antyufeyev , I. Shmeld , V. Bezrukovs , M. Bleiders , A. Orbidans , A. Aberfelds , V. Shulga

We have examined methanol emission from Orion KL with of the {\em Herschel}/HIFI instrument, and detected two methanol bands centered at 524 GHz and 1061 GHz. The 524 GHz methanol band (observed in HIFI band 1a) is dominated by the isolated…

We present the results of unbiased 22 GHz H2O water and 44 GHz class I CH3OH methanol maser surveys in the central 7x10 arcmin area of NGC 1333 and two additional mapping observations of a 22 GHz water maser in a ~3x3arcmin area of the…

Astrophysics of Galaxies · Physics 2015-06-22 A-Ran Lyo , Jongsoo Kim , Do-Young Byun , Ho-Gyu Lee

We present results of the investigations of the properties of the methanol $J_1 - J_0$ A$^{-+}$ line series motivated by the recent serendipitous detection of the maser emission in the $14_1 - 14_0$ A$^{-+}$ line at 349~GHz in S255IR-SMA1…

Astrophysics of Galaxies · Physics 2022-03-30 Svetlana V. Salii , Igor I. Zinchenko , Sheng-Yuan Liu , Andrej M. Sobolev , Artis Aberfelds , Yu-Nung Su

Aims. We report the discovery of periodic maser variability of an unusual pattern in the high-mass young stellar object G26.598-0.024. Methods. A ten-year monitoring of the 6.7 GHz methanol maser was carried out with the Torun 32 m radio…

Astrophysics of Galaxies · Physics 2025-08-14 P. Wolak , M. Szymczak , A. Kobak , A. Varma , A. Bartkiewicz , J. O. Chibueze , B. Stecklum , C. J. Ugwu

Methanol masers at 6.7 GHz are associated with high-mass star-forming regions (HMSFRs) and often have mid-infrared (MIR) counterparts characterized by extended emission at 4.5 $\mu$m, which likely traces outflows from massive young stellar…

Astrophysics of Galaxies · Physics 2014-05-08 Anna Bartkiewicz , Marian Szymczak , Huib van Langevelde

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…

Astrophysics · Physics 2007-05-23 A. Bartkiewicz , M. Szymczak , H. J. van Langevelde

We present $\sim1-4"$ resolution Very Large Array (VLA) observations of four CH$_3$OH $J_2-J_1$-$E$ 25~GHz transitions ($J$=3, 5, 8, 10) along with 1.3~cm continuum toward 20 regions of active massive star formation containing Extended…