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相关论文: 6.7GHz methanol maser variability in Cepheus A

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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…

星系天体物理 · 物理学 2020-01-08 Sonu Tabitha Paulson , Jagadheep D. Pandian

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…

天体物理学 · 物理学 2009-11-13 J. D. Pandian , S. Leurini , K. M. Menten , A. Belloche , P. F. Goldsmith

We have used the Australia Telescope Compact Array to undertake the first high-resolution observations of the 19.9-GHz methanol maser transition. The emission is coincident with the location of the targeted 6.7-GHz methanol masers to within…

星系天体物理 · 物理学 2015-06-16 Vasaant Krishnan , Simon Ellingsen , Maxim Voronkov , Shari Breen

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…

星系天体物理 · 物理学 2014-06-04 L. Olmi , E. D. Araya , P. Hofner , S. Molinari , J. Morales Ortiz , L. Moscadelli , M. Pestalozzi

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…

A survey of young bipolar outflows in regions of low-to-intermediate-mass star formation has been carried out in two class I methanol maser transitions: 7_0-6_1A+ at 44 GHz and 4_{-1}-3_0E at 36 GHz. We detected narrow features towards NGC…

星系天体物理 · 物理学 2015-05-18 S. V. Kalenskii , L. E. B. Johansson , P. Bergman , S. Kurtz , P. Hofner , C. M. Walmsley , V. I. Slysh

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…

We investigate the kinematics of high mass protostellar objects within the high mass star forming region IRAS 19410+2336. We performed high angular resolution observations of 6.7-GHz methanol and 22 GHz water masers using the MERLIN…

星系天体物理 · 物理学 2021-05-25 M. S. Darwish , K. A. Edris , A. M. S. Richards , S. Etoka , M. S. Saad , M. M. Beheary , G. A Fuller

The University of Tasmania Mt Pleasant 26-m and Ceduna 30-m radio telescopes have been used to search for 6.7-GHz class II methanol masers towards two hundred GLIMPSE sources. The target regions were selected on the basis of their…

天体物理学 · 物理学 2008-11-26 S. P. Ellingsen

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+…

天体物理学 · 物理学 2009-11-10 S. P. Ellingsen , D. M. Cragg , J. E. J. Lovell , A. M. Sobolev , P. D. Ramsdale , P. D. Godfrey

We report the negative results from a search for 6.7 GHz methanol masers in the nearby spiral galaxy M33. We observed 14 GMCs in the central 4 kpc of the Galaxy, and found 3 sigma upper limits to the flux density of ~9 mJy in spectral…

天体物理学 · 物理学 2009-11-13 P. F. Goldsmith , J. D. Pandian , A. A. Deshpande

We report the detection of emission from the 6.7 GHz 5(1)-6(0)A+ transition of methanol towards the center of the nearby galaxy NGC4945. This is the first detection of emission in this transition beyond the local group. The isotropic…

星系天体物理 · 物理学 2018-10-25 Simon Ellingsen , Tiege McCarty , Shari Breen , Maxim Voronkov

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…

星系天体物理 · 物理学 2014-05-08 Anna Bartkiewicz , Marian Szymczak , Huib van Langevelde

We present the discovery of the simultaneous flux variation of a massive young stellar object (MYSO) G036.70+00.09 (G036.70) both in the maser emission and mid-infrared (MIR;$\lambda=3$--$5$~$\mu$m) bands. Utilizing the ALLWISE and NEOWISE…

太阳与恒星天体物理 · 物理学 2022-09-07 Mizuho Uchiyama , Kohei Ichikawa , Koichiro Sugiyama , Yoshihiro Tanabe , Yoshinori Yonekura

We have used the Australia Telescope National Facility Mopra 22-m antenna to search for 37.7-GHz (7(-2) - 8(-1}E) methanol masers towards a sample of thirty six class II methanol masers. The target sources are the most luminous class II…

星系天体物理 · 物理学 2015-06-12 S. P. Ellingsen , S. L. Breen , M. A. Voronkov , J. R. Dawson

We have detected emission from both the 4_{-1}-3_{0} E (36.2~GHz) class I and 7_{-2}-8_{-1} E (37.7~GHz) class II methanol transitions towards the centre of the closest ultra-luminous infrared galaxy Arp 220. The emission in both the…

星系天体物理 · 物理学 2015-06-23 Xi Chen , Simon P. Ellingsen , Willem A. Baan , Hai-Hua Qiao , Juan Li , Tao An , Shari L. Breen

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…

太阳与恒星天体物理 · 物理学 2015-06-05 J. D. Pandian , F. Wyrowski , K. M. Menten

Temporal photometric variations at near infrared to submillimeter wavelengths have been found in low-mass young stellar objects. These phenomena are generally interpreted as accretion events of star-disk systems with varying accretion…

星系天体物理 · 物理学 2018-08-15 Sheng-Yuan Liu , Yu-Nung Su , Igor Zinchenko , Kuo-Song Wang , Yuan Wang

An updated catalog consisting of 1092 6.7-GHz methanol maser sources was reported in this work. Additionally, the NH3 (1, 1), NH3 (2, 2), and NH3 (3, 3) transitions were observed towards 214 star forming regions using the Shanghai Tianma…

星系天体物理 · 物理学 2024-03-01 Tian Yang , Xi Chen , Yan-Kun Zhang , Xu-Jia Ouyang , Shi-Min Song , Jia-Liang Chen , Ying Lu

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…

星系天体物理 · 物理学 2015-05-19 J. D. Pandian , E. Momjian , Y. Xu , K. M. Menten , P. F. Goldsmith