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Related papers: Precise Positions of Methanol Masers

200 papers

We report on the interferometric detection of 36.2 GHz Class I methanol emission with the new 27-40 GHz Ka band receivers available on the Expanded Very Large Array (EVLA). The brightness temperatures of the interferometric 36 GHz…

Astrophysics of Galaxies · Physics 2015-05-18 Lorant O. Sjouwerman , Ylva M. Pihlstrom , Vincent L. Fish

Methanol masers at 6.7 GHz are known to be tracers of high-mass star formation in our Galaxy. In this paper, we study the large scale physical conditions in the star forming clumps/cores associated with 6.7 GHz methanol masers using…

Solar and Stellar Astrophysics · Physics 2015-06-05 J. D. Pandian , F. Wyrowski , K. M. Menten

Astrophysical masers are one of the most readily detected signposts of high-mass star formation. Their presence indicates special conditions, probably indicative of a specific evolutionary phase. Masers also represent the ultimate…

Astrophysics · Physics 2007-05-23 Simon Ellingsen

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

Context: Methanol masers at 6.7GHz are recognised markers of high-mass star formation regions. The study of their distribution in the Galaxy gives important insights into the star formation activity of the Milky Way. We present a…

Astrophysics · Physics 2009-11-11 Michele R. Pestalozzi , A. Chrysostomou , J. Collett , V. Minier , J. Conway , R. Booth

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 have used the Australia Telescope Compact Array (ATCA) to conduct further observations of the 36.2-GHz ($4_{-1}\rightarrow3_0$E) methanol transition towards the nearby active galaxy NGC 4945. These observations have led to a more…

Astrophysics of Galaxies · Physics 2018-08-22 Tiege P. McCarthy , Simon P. Ellingsen , Shari L. Breen , Christian Henkel , Maxim A. Voronkov

We have observed a sample of 288 molecular outflow sources including 123 high-mass and 165 low-mass sources to search for class I methanol masers at 95 GHz transition and to investigate relationship between outflow characteristics and class…

Solar and Stellar Astrophysics · Physics 2015-06-12 Cong-Gui Gan , Xi Chen , Zhi-Qiang Shen , Ye Xu , Bing-Gang Ju

We have investigated the central region of NGC 253 for the presence of 84.5-GHz ($5_{-1}\rightarrow4_0$E) methanol emission using the Australia Telescope Compact Array. We present the second detection of 84.5-GHz class~I methanol maser…

Astrophysics of Galaxies · Physics 2018-11-21 Tiege P. McCarthy , Simon P. Ellingsen , Shari L. Breen , Maxim A. Voronkov , Xi Chen

We present milliarcsecond resolution images of the 6.7 and 12.2 GHz methanol maser emission associated with the well-known star formation region NGC 6334F. The images agree well with previous lower resolution observations, but detect…

Full polarization measurements of 1665 and 1667-MHz OH masers at sites of massive star formation have been made with the Parkes 64-m radio telescope. Here we present the resulting spectra for 104 northerly sources. For more than 20 masers…

Astrophysics of Galaxies · Physics 2014-02-12 J. L. Caswell , J. A. Green , C. J. Phillips

Ground-state OH masers identified in the Southern Parkes Large-Area Survey in Hydroxyl were observed with the Australia Telescope Compact Array to obtain positions with high accuracy ($\sim$1\,arcsec). We classified these OH masers into…

Astrophysics of Galaxies · Physics 2017-02-22 Hai-Hua Qiao , Andrew J. Walsh , Zhi-Qiang Shen , Joanne R. Dawson

We present 1" resolution CARMA observations of the 3mm continuum and 95 GHz methanol masers toward 14 candidate high mass protostellar objects (HMPOs). Dust continuum emission is detected toward seven HMPOs, and methanol masers toward 5…

Astrophysics of Galaxies · Physics 2011-02-11 S. Schnee , J. Carpenter

We report on the presence of 6.7-GHz methanol masers, known tracers of high-mass star formation, in the 3-kpc arms of the inner Galaxy. We present 49 detections from the Methanol Multibeam Survey, the largest Galactic plane survey for…

Astrophysics of Galaxies · Physics 2009-04-29 J. A. Green , N. M. McClure-Griffiths , J. L. Caswell , S. P. Ellingsen , G. A. Fuller , L. Quinn , M. A. Voronkov

This work presents a study of the milliarcsecond structure of the 6.7 GHz methanol masers at high-velocity resolution (0.09 km s^(-1)) in four high-mass star-forming regions: G16.59-0.05, G23.01-0.41, IRAS20126+4104, and AFGL5142. We…

Solar and Stellar Astrophysics · Physics 2015-05-30 Luca Moscadelli , Alberto Sanna , Ciriaco Goddi

Four Class I maser sources were detected at 44, 84, and 95 GHz toward chemically rich outflows in the regions of low-mass star formation NGC 1333I4A, NGC 1333I2A, HH25, and L1157. One more maser was found at 36 GHz toward a similar outflow,…

Astrophysics of Galaxies · Physics 2015-06-04 S. V. Kalenskii , V. I. Slysh , L. E. B. Johansson , P. Bergman , S. Kurtz , P. Hofner , C. M. Walmsley

We present results on simultaneous observations of Class~I methanol masers at 25, 36, and 44 GHz towards 22 Galactic targets carried out with the Effelsberg 100-m telescope. The study investigates relations between the hyperfine (HF)…

We have used the Australia Telescope Compact Array (ATCA) to make a sensitive (5-$\sigma$ $\simeq$ 100 mJy) search for maser emission from the 4765-MHz $^2\Pi_{1/2}$ F=1$\to$0 transition of OH. Fifty five star formation regions were…

Astrophysics · Physics 2009-11-07 R. Dodson , S. P. Ellingsen , M. A. Voronkov

Milliarcsecond VLBI maps of regions containing 6.7 GHz methanol maser emission have lead to the recent discovery of ring-like distributions of maser spots and the plausible hypothesis that they may be tracing circumstellar disks around…

Solar and Stellar Astrophysics · Physics 2015-06-05 James M. De Buizer , Anna Bartkiewicz , Marian Szymczak

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…