相关论文: Non-equilibrium excitation of methanol in Galactic…
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…
We report the discovery of a widespread population of collisionally excited methanol J = 4_{-1} to 3$_0 E sources at 36.2 GHz from the inner 66'x18' (160x43 pc) of the Galactic center. This spectral feature was imaged with a spectral…
Class\,I methanol masers provide sensitive information about the shocked environment around star-forming regions. Among the brightest Class~I methanol masers, we have those in the $J_{-1}\rightarrow(J-$ 1)$_{0}-E$ line series, currently…
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…
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,…
Class I methanol masers are collisionally pumped and are generally correlated with outflows in star forming sites in the Galaxy. Using the VLA in its A-array configuration, we present a spectral line survey to identify methanol…
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 247-GHz molecular line observations of methanol (CH$_3$OH) toward sixteen massive star-forming regions, using the APEX telescope with an angular resolution of $25''$. The sample covers a range of evolutionary states, including…
We present the unambiguous discovery of six new class II methanol maser transitions, three of which are torsionally excited (vt=1). The newly discovered 6.18-GHz 17_-2 -> 18_-3 E (vt=1), 7.68-GHz 12_4 -> 13_3 A- (vt=0), 7.83-GHz 12_4 ->…
Context: We investigated the molecular gas associated with 6.7 GHz methanol masers throughout the Galaxy using a J=1-0 transition of the CO isotopologues. Methods:Using the 13.7-meter telescope at the Purple Mountain Observatory (PMO), we…
Methanol masers are often detected in regions of intense star formation. Several studies in the last decade indicate that they may even be the earliest signpost of a high-mass star-forming region. Their powerful emission make them very good…
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,…
Using the Haystack Observatory 37-m radio telescope we have undertaken a search for emission in the 2(0)-3(1)E rotational transition of methanol in its first torsionally excited state (v_t=1) at 44.9 GHz. We examined seven galactic sources…
We have used the Australia Telescope National Facility Mopra 22m millimetre telescope to search for emission from the 85.5-GHz and 86.6-GHz transitions of methanol. The search was targeted towards 22 star formation regions which exhibit…
We have used the Australia Telescope Compact Array (ATCA) to undertake the first high angular resolution observations of 37.7-GHz ($7_{-2} - 8_{-1}E$) methanol masers towards a sample of eleven high-mass star formation regions which host…
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…
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…
We have used the Swedish ESO Submillimetre Telescope (SEST) to search for new class II methanol maser transitions towards the southern source G345.01+1.79. Over a period of 5 days we observed 11 known or predicted class II methanol maser…
A sensitive search for 6.7--GHz methanol maser emission has been made towards 10 galaxies that have yielded detectable microwave molecular--line transitions. These include several which show OH megamaser or superluminous \water\/ maser…
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…