中文
相关论文

相关论文: Hyperfine structure of the methanol molecule as tr…

200 篇论文

High-dispersion (channel width 0.015 km s^-1) laboratory spectroscopy of the torsion-rotation lines J_2 - J_1 (J = 2 - 6) in the ground torsional state (vt = 0) of the E-type methanol demonstrates multicomponent hyperfine splitting patterns…

原子物理 · 物理学 2023-10-13 J. S. Vorotyntseva , S. A. Levshakov

We have used the Australia Telescope Compact Array (ATCA) to make the first high resolution observations of a large sample of class~I methanol masers in the 95-GHz ($8_0$--$7_1$A$^+$) transition. The target sources consist of a…

星系天体物理 · 物理学 2018-03-28 Tiege P. McCarthy , Simon P. Ellingsen , Maxim A. Voronkov , Giuseppe Cimo

The Australia Telescope Compact Array (ATCA) has been used for high angular resolution imaging of 71 southern class I methanol maser sources quasi-simultaneously at 36 and 44 GHz. The data reveal a high level of morphological and…

星系天体物理 · 物理学 2015-06-18 M. A. Voronkov , J. L. Caswell , S. P. Ellingsen , J. A. Green , S. L. Breen

Context. Class II methanol masers at 6.7 and 12.2 GHz occur close to high-mass young stellar objects (HMYSOs). When they are observed simultaneously, such studies may contribute to refining the characterisation of local physical conditions.…

星系天体物理 · 物理学 2021-04-28 M. Durjasz , M. Szymczak , P. Wolak , A. Bartkiewicz

We investigate which structures the 6.7 GHz methanol masers trace in the environment of high-mass protostar candidates by observing a homogenous sample of methanol masers selected from Torun surveys. We also probed their origins by looking…

星系天体物理 · 物理学 2015-05-13 A. Bartkiewicz , M. Szymczak , H. J. van Langevelde , A. M. S. Richards , Y. M. Pihlstrom

We present observations of the 36- (4_-1 -> 3_0E) and 84-GHz (5_-1 -> 4_0 E) class I methanol maser transitions towards a sample of 94 known class I sites. These observations resulted in 93 and 92 detections in the 84- and 36-GHz…

星系天体物理 · 物理学 2019-01-30 Shari Breen , Yanett Contreras , Joanne Dawson , Simon Ellingsen , Maxim Voronkov , Tiege McCarthy

The polarized emission of astrophysical masers, especially OH and methanol lines, is an effective tool to study the magnetic field in high-mass star-forming regions. The magnetic field strength measurement via the Zeeman effect of OH maser…

星系天体物理 · 物理学 2025-08-21 A. Kobak , G. Surcis , A. Bartkiewicz , W. H. T. Vlemmings , M. Szymczak

We report accurate laboratory measurements of selected methanol transition frequencies between 0.834 and 230 GHz in order to facilitate astronomical velocity analyses. New data have been obtained between 10 and 27 GHz and between 60 and 119…

天体物理学 · 物理学 2011-03-02 H. S. P. Mueller , K. M. Menten , H. Maeder

We report a simultaneous 44 and 95 GHz class I methanol maser survey toward 144 sources from the 95 GHz class I methanol maser catalog. The observations were made with the three telescopes of the Korean very long baseline interferometry…

太阳与恒星天体物理 · 物理学 2020-05-20 Wenjin Yang , Ye Xu , Yoon Kyung Choi , Simon P. Ellingsen , Andrej M. Sobolev , Xi Chen , Jingjing Li , Dengrong Lu

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…

{The variability study of 6.7\,GHz methanol masers has become a useful way to improve our understanding of the physical conditions in high-mass star-forming regions.} {Based on the single-dish monitoring using the Irbene telescopes, we…

星系天体物理 · 物理学 2023-07-10 A Aberfelds , A Bartkiewicz , M Szymczak , J Šteinbergs , G Surcis , A Kobak , M Durjasz , I Shmeld

We report the first detection of a methanol maser in the 10(1)-9(2)A- transition at 23.4 GHz, discovered during the H2O southern Galactic Plane Survey (HOPS) with the 22-m Mopra radio telescope. In the region covered by HOPS, the 23.4 GHz…

Among the tracers of the earliest phases in the massive star formation process, methanol masers have gained increasing importance. The phenomenological distinction between Class I and II methanol masers is based on their spatial association…

星系天体物理 · 物理学 2015-05-18 F. Fontani , R. Cesaroni , R. S. Furuya

We present results from calculations of the physical conditions necessary for the occurrence of 36.169 ($4_{-1}-3_{0}\, E$), 44.070 ($7_{0}-6_{1}\,A^+$), 84.521 ($5_{-1}-4_{0}\,E$), and 95.169 ($8_{0}-7_{1}\,A^+$) GHz methanol (CH$_3$OH)…

太阳与恒星天体物理 · 物理学 2015-06-22 Bridget C. McEwen , Ylva M. Pihlström , Loránt O. Sjouwerman

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,…

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…

太阳与恒星天体物理 · 物理学 2016-12-07 Bridget McEwen , Loránt Sjouwerman , Ylva Pihlström

Recently, the extremely sensitive torsion-rotation transitions in methanol have been used to set a tight constraint on a possible variation of the proton-to-electron mass ratio over cosmological time scales. In order to improve this…

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

The methanol molecule CH3OH has a complex microwave spectrum with a large number of very strong lines. This spectrum includes purely rotational transitions as well as transitions with contributions of the internal degree of freedom…

宇宙学与河外天体物理 · 物理学 2013-06-12 S. A. Levshakov , M. G. Kozlov , D. Reimers

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…

‹ 上一页 1 2 3 10 下一页 ›