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Related papers: Periodic variations in 6.7-GHz methanol masers

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We present the results of a monitoring campaign using the KAT-7 and HartRAO 26m telescopes, of hydroxyl, methanol and water vapour masers associated with the high-mass star forming region G9.62+0.20E. Periodic flaring of the main line…

Solar and Stellar Astrophysics · Physics 2019-03-20 S. Goedhart , R. van Rooyen , D. J. van der Walt , J. P. Maswanganye , A. Sanna , G. C. MacLeod , S. P. van den Heever

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

Ring-like distributions of the 6.7 GHz methanol maser spots at milliarcsecond scales represent a family of molecular structures of unknown origin associated with high-mass young stellar objects (HMYSOs). We aim to study G23.657-00.127,…

Astrophysics of Galaxies · Physics 2020-05-06 Anna Bartkiewicz , Alberto Sanna , Marian Szymczak , Luca Moscadelli , Huib Jan van Langevelde , Pawel Wolak

We present a comprehensive analysis of the periodic flares observed in the 6.7 GHz methanol transition in G22.356+0.066, utilizing the Maxwell-Bloch equations (MBEs) as a framework to model these phenomena. By solving the one-dimensional…

High Energy Astrophysical Phenomena · Physics 2024-09-17 T. Rashidi , V. Anari , A. Bartkiewicz , P. Wolak , M. Szymczak , F. Rajabi

(Abridged) Recently, the magnetic field induced Zeeman splitting was measured for the strongest known 6.7 GHz methanol maser, which arises in the massive star forming region G09.62+0.20. This maser is one of a handful of periodically…

Astrophysics of Galaxies · Physics 2015-05-13 W. H. T. Vlemmings , S. Goedhart , M. J. Gaylard

We have used the NASA Tidbinbilla 70-m antenna to search for emission from the 2(1)-3(0)E 19.9-GHz transition of methanol. The search was targeted towards 22 star formation regions which exhibit maser emission in the 107.0-GHz 3(1)-4(0)A+…

We present the results of daily monitoring of 6.7 GHz methanol maser in Cepheus A (Cep A) using Yamaguchi 32-m radio telescope as well as the results of imaging observations conducted with the JVN (Japanese VLBI Network). We indentified…

We report the detection of bursts of 6.7 GHz methanol maser emission in a high-mass star-forming region, G33.64-0.21. One of the spectral components of the maser in this source changed its flux density by 7 times that of the previous day,…

We report the detection of new 12.178, 12.229, 20.347, and 23.121 GHz methanol masers in the massive star-forming region G358.93-0.03, which are flaring on similarly short timescales (days) as the 6.668 GHz methanol masers also associated…

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

This is the second paper in a series of catalogues of 22-GHz water maser observations towards the 6.7-GHz methanol masers from the Methanol Multibeam (MMB) Survey. In this paper we present our water maser observations made with the…

Astrophysics of Galaxies · Physics 2016-03-23 A. M. Titmarsh , S. P. Ellingsen , S. L. Breen , J. L. Caswell , M. A. Voronkov

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…

Through a series of observations with the Australia Telescope Compact Array we have monitored the variability of ground-state hydroxyl maser emission from G12.889+0.489 in all four Stokes polarisation products. These observations were…

Astrophysics of Galaxies · Physics 2015-06-05 J. A. Green , J. L. Caswell , M. A. Voronkov , N. M. McClure-Griffiths

A new methanol maser line 6(-1)-5(0)E at 133 GHz was detected with the 12-m Kitt Peak radio telescope using remote observation mode from Moscow. Moderately strong, narrow maser lines were found in DR21(OH), DR21-W, OMC-2, M8E, NGC2264,…

Astrophysics · Physics 2009-10-30 V. I. Slysh , S. V. Kalenskii , I. E. Val'tts , V. V. Golubev

We present results of a multi-epoch monitoring program on variability of 6$\,$cm formaldehyde (H$_2$CO) masers in the massive star forming region NGC$\,$7538$\,$IRS$\,$1 from 2008 to 2015 conducted with the GBT, WSRT, and VLA. We found that…

Astrophysics of Galaxies · Physics 2017-11-01 N. Andreev , E. D. Araya , I. M. Hoffman , P. Hofner , S. Kurtz , H. Linz , L. Olmi , I. Lorran-Costa

The Australia Telescope Compact Array (ATCA) has been used to make the first full polarization observations of 6.7 GHz methanol masers. Linear polarization was detected towards all four sources observed, at levels between a few and 10%,…

Astrophysics · Physics 2007-05-23 S. P. Ellingsen

Recent studies have shown that 6.7 GHz methanol maser flares can be a powerful tool for verifying the mechanisms of maser production and even the specific signatures of accretion rate changes in the early stages of high-mass star formation.…

The Australia Telescope Compact Array (ATCA) has been used to image class I methanol masers at 9.9, 25 (a series from J=2 to J=9), 84, 95 and 104 GHz located in the vicinity of IRAS 16547-4247 (G343.12-0.06), a luminous young stellar object…

We have used the ATNF Mopra antenna and the SEST antenna to search in the directions of several class II methanol maser sources for emission from six methanol transitions in the frequency range 85-115 GHz. The transitions were selected from…

Emission from the 6.7 GHz methanol maser transition is very strong, is relatively stable, has small internal motions, and is observed toward numerous massive star-forming regions in the Galaxy. Our goal is to perform high-precision…

Astrophysics of Galaxies · Physics 2015-05-14 K. L. J. Rygl , A. Brunthaler , M. J. Reid , K. M. Menten , H. J. van Langevelde , Y. Xu