English
Related papers

Related papers: Testing maser-based evolutionary schemes: A new se…

200 papers

Intriguing work on observations of 4.83 GHz formaldehyde (H2CO) absorptions and 4.87 GHz H110a radio recombination lines (RRLs) towards 6.7 GHz methanol (CH3OH) maser sources is presented. Methanol masers provide ideal sites to probe the…

Solar and Stellar Astrophysics · Physics 2015-06-18 Daniel. Okoh , Jarken. Esimbek , Jian. Jun. Zhou , Xin. Di. Tang , Augustine. Chukwude , Johnson. Urama , Pius. Okeke

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 studied class I methanol masers in the transition 7_0-6_1 A+ at the frequency 44 GHz with the VLA. The observations on the VLA were made with the angular resolution 0''.1, which was the highest at the moment. It was shown that the masers…

Astrophysics · Physics 2007-05-23 V. I. Slysh , I. E. Val'tts , S. V. Kalenskii

Methanol masers at 6.7 GHz are well known tracers of high-mass star-forming regions. However, their origin is still not clearly understood. We aimed to determine the morphology and velocity structure for a large sample of the maser emission…

Astrophysics of Galaxies · Physics 2016-03-02 Anna Bartkiewicz , Marian Szymczak , Huib J. van Langevelde

We have conducted a Galactic plane survey of methanol masers at 6668 MHz using a 7-beam receiver on the Parkes telescope. Here we present results from the first part, which provides sensitive unbiased coverage of a large region around the…

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…

Astrophysics · Physics 2009-11-13 P. F. Goldsmith , J. D. Pandian , A. A. Deshpande

We present the results of an unbiased survey for 6.7 GHz methanol masers in the Galactic plane carried out using the 305 m Arecibo radio telescope. A total of 18.2 square degrees was surveyed with uniform sampling at 35.2 deg < l < 53.7…

Astrophysics · Physics 2008-11-26 Jagadheep D. Pandian , Paul F. Goldsmith , Avinash A. Deshpande

We have selected the positions of 54 6.7GHz methanol masers from the Methanol Multibeam Survey catalogue, covering a range of longitudes between $20^{\circ}$ and $34^{\circ}$ of the Galactic Plane. These positions were mapped in the J=3-2…

We report on a large 44 GHz ($7_0-6_1$ A$^+$) methanol (CH$_3$OH) maser survey of the Galactic Center (GC). The Karl G. Jansky Very Large Array was used to search for CH$_3$OH maser emission covering a large fraction of the region around…

Solar and Stellar Astrophysics · Physics 2016-12-07 Bridget McEwen , Loránt Sjouwerman , Ylva Pihlström

Fifty-one objects in the 5_{-1}-4_0E methanol line at 84.5 GHz were detected during a survey of Class I maser sources. Narrow maser features were found in 17 of these. Broad quasi-thermal lines were detected towards other sources. One of…

Astrophysics · Physics 2009-11-06 S. V. Kalenskii , V. I. Slysh , I. E. Val'tts , A. Winngerg , L. E. B. Johansson

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

Six young bipolar outflows in regions of low-to-intermediate-mass star formation were observed in the 7_0-6_1A+, 8_0-7_1A+, and 5_{-1}-4_0E methanol lines at 44, 95, and 84 GHz, respectively. Narrow features were detected towards NGC…

Astrophysics · Physics 2009-11-11 S. V. Kalenskii , V. G. Promyslov , V. I. Slysh , P. Bergman , A. Winnberg

The Central Molecular Zone (CMZ) spans the inner ~450 pc (3 degrees) of our Galaxy. This region is defined by its enhanced molecular emission and contains 5% of the entire Galaxy's molecular gas mass. However, the number of detected star…

Astrophysics of Galaxies · Physics 2019-01-16 Matthew Rickert , F. Yusef-Zadeh , J. Ott

We report a survey with the Purple Mountain Observatory (PMO) 13.7-m radio telescope for class I methanol masers from the 95 GHz (8_0 - 7_1 A^+) transition. The 214 target sources were selected by combining information from both the Spitzer…

Astrophysics of Galaxies · Physics 2015-06-04 Xi Chen , Simon P. Ellingsen , Jin-Hua He , Ye Xu , Cong-Gui Gan , Zhi-Qiang Shen , Tao An , Yan Sun , Bing-Gang Ju

We report the result of a systematic methanol observation toward IRAS 19312+1950. The properties of the SiO, H2O and OH masers of this object are consistent with those of mass-losing evolved stars, but some other properties are difficult to…

Solar and Stellar Astrophysics · Physics 2015-08-06 Jun-ichi Nakashima , Andrej M. Sobolev , Svetlana V. Salii , Yong Zhang , Bosco H. K. Yung , Shuji Deguchi

Water masers are common in star-forming regions (SFRs), with the 22.235 GHz transition widely detected in both high- and low-mass protostars. In contrast, (sub)millimeter water maser transitions remain poorly studied, especially in low-mass…

Astrophysics of Galaxies · Physics 2025-09-17 P. K. Humire , C. Goddi , G. N. Ortiz-León , A. Hernández-Gómez , J-C Loison

The Methanol MultiBeam survey (MMB) provides the most complete sample of Galactic massive young stellar objects (MYSOs) hosting 6.7GHz class II methanol masers. We characterise the properties of these maser sources using dust emission…

Methanol (CH3OH) is one of the most abundant interstellar molecules, offering a vast number of transitions to be studied, including many maser lines. While the strongest Galactic CH3OH lines, the so-called class II masers, show no…

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

The Cygnus X complex is covered by the Global View of Star Formation in the Milky Way (GLOSTAR) survey, an unbiased radio-wavelength Galactic plane survey, in 4--8 GHz continuum radiation and several spectral lines. The GLOSTAR survey…