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From targeted observations of ground-state OH masers towards 702 Multibeam (MMB) survey 6.7-GHz methanol masers, between Galactic longitudes 186$^{\circ}$ through the Galactic centre to 20$^{\circ}$, made as part of the `MAGMO' project, we…

Astrophysics of Galaxies · Physics 2020-01-29 C. S. Ogbodo , J. A. Green , J. R. Dawson , S. L. Breen , S. A. Mao , N. M. McClure-Griffiths , T. Robishaw , L. Harvey-Smith , .

We derive accurate proper motions of the CH3OH 12 GHz masers towards the W3(OH) UCHII region, employing seven epochs of VLBA observations spanning a time interval of about 10 yr. The achieved velocity accuracy is of the order of 0.1 km/s,…

Solar and Stellar Astrophysics · Physics 2015-05-18 Luca Moscadelli , Ye Xu , Xi Chen

We analyze observational data on methanol masers in the disks of young massive stellar objects in the massive star formation regions: NGC6334I, G33.641-0.228, G12.89+0.49. Special attention is paid to analysis of the magnetic fields and…

Solar and Stellar Astrophysics · Physics 2025-11-14 P. I. Pavlova , S. A. Khaibrakhmanov , A. M. Sobolev

We report the detection of the satellite 18 cm OH lines at 1612 and 1720 MHz in the z=0.2467 molecular absorption system toward the radio source PKS 1413+135. The two OH lines are conjugate; the 1612 MHz line is seen in absorption while the…

Astrophysics · Physics 2009-11-10 Jeremy Darling

We aim to detect the magnetic field and infer its properties around four AGB stars using H$_2$O maser observations. The sample we observed consists of the following sources: the semi-regular variable RT Vir and the Mira variables AP Lyn, IK…

Solar and Stellar Astrophysics · Physics 2015-06-15 M. L. Leal-Ferreira , W. H. T. Vlemmings , A. Kemball , N. Amiri

We present Giant Metrewave Radio Telescope (GMRT) observations of OH absorption in B3~1504+377 ($z \sim 0.673$) and PKS 1413+135 ($z \sim 0.247$). OH has now been detected in absorption towards four intermediate redshift systems, viz. the…

Astrophysics · Physics 2009-11-07 Nissim Kanekar , Jayaram N Chengalur

We report on WSRT observations of HI and OH absorption at z=0.885 towards the radio lens PKS 1830-21, mm wave transitions of several molecular species have already been observed at this redshift. At mm wavelengths the source structure is…

Astrophysics · Physics 2011-05-23 Jayaram N. Chengalur , A. G. de Bruyn , D. Narasimha

Context. Magnetic fields are key to understand galaxy evolution, regulating stellar feedback and star formation in galaxies. Aims. We probe the origin of magnetic fields in late-type galaxies, measuring magnetic field strengths, exploring…

We present the results of the observations of the (J,K)=(1,1) and the (J,K)=(2,2) inversion transitions of the NH3 molecule toward a large sample of 40 regions with molecular or optical outflows, using the 37 m radio telescope of the…

Solar and Stellar Astrophysics · Physics 2015-05-27 I. Sepúlveda , G. Anglada , R. Estalella , R. López , J. M. Girart , J. Yang

A study of the distribution of OH gas in the central region of the nearby active starburst galaxy M82 has confirmed two previously known bright masers and revealed several new main line masers. Three of these are seen only at 1665 MHz, one…

Astrophysics · Physics 2009-11-13 M. K. Argo , A. Pedlar , R. J. Beswick , T. W. B. Muxlow

A flare of OH maser emission was discovered in W75N in 2000. Its location was determined with the VLBA to be within 110 au from one of the ultracompact H II regions, VLA2. The flare consisted of several maser spots. Four of the spots were…

Astrophysics · Physics 2009-11-11 V. I. Slysh , V. Migenes

We gave an extensive study for the quasi-periodic perturbations on the time profiles of the line of sight (LOS) magnetic field in 10x10 sub-areas in a solar plage region (corresponds to a facula on the photosphere). The perturbations are…

Solar and Stellar Astrophysics · Physics 2022-04-20 Haisheng Ji , Parida Hashim , Zhenxiang Hong , Zhe Xu , Jinhua Shen , Kaifan Ji , Wenda Cao

We have carried out a multi-epoch simultaneous survey of 22 GHz H$_2$O and 44 GHz Class I CH$_3$OH masers toward 103 ultracompact HII regions (UCHIIs) between 2010 and 2017. We detected H$_2$O and CH$_3$OH maser emission in 74 (72%) and 55…

Solar and Stellar Astrophysics · Physics 2019-09-04 Won-Ju Kim , Kee-Tae Kim , Kwang-Tae Kim

We have used the NRAO Very Long Baseline Array (VLBA) to image OH(1720 MHz) masers in the supernova remnants W28 and W44 at a resolution of 40 mas. We also used MERLIN to observe the same OH(1720 MHz) masers in W44 at a resolution of 290 x…

Astrophysics · Physics 2009-10-31 M. J. Claussen , W. M. Goss , D. A. Frail , K. Desai

We have measured the Zeeman splitting of OH megamaser emission at 1667 MHz from five (ultra)luminous infrared galaxies ([U]LIRGs) using the 305 m Arecibo telescope and the 100 m Green Bank Telescope. Five of eight targeted galaxies show…

Astrophysics · Physics 2009-11-13 Timothy Robishaw , Eliot Quataert , Carl Heiles

The BL Lac PKS 1413+135 was observed by the Large Survey Project "MeerKAT Absorption Line Survey" (MALS) in the L-band, at 1139 MHz and 1293-1379 MHz, targeting the HI and OH lines in absorption at z = 0.24671. The radio continuum is…

Magnetic fields have only recently been included in theoretical simulations of high-mass star formation. The simulations show that magnetic fields can play a crucial role not only in the formation and dynamics of molecular outflows, but…

Solar and Stellar Astrophysics · Physics 2015-03-10 G. Surcis , W. H. T. Vlemmings , H. J. van Langevelde , B. Hutawarakorn Kramer , A. Bartkiewicz , H. Engelkamp

We present global VLBI observations of the first-excited state OH masers in the massive star-forming region Onsala 1 (ON 1). The 29 masers detected are nearly all from the 6035 MHz transition, and nearly all are identifiable as Zeeman pair…

Astrophysics of Galaxies · Physics 2010-04-23 Vincent L. Fish , Loránt O. Sjouwerman

We present a study of the line-of-sight magnetic fields in five large-diameter Galactic HII regions. Using the Faraday rotation of background polarized radio sources, as well as dust-corrected H-alpha surface brightness as a probe of…

Astrophysics of Galaxies · Physics 2015-05-28 Lisa Harvey-Smith , Gregory J. Madsen , Bryan M. Gaensler

The hydroxyl radical (OH) is found in various environments within the interstellar medium (ISM) of the Milky Way and external galaxies, mostly either in diffuse interstellar clouds or in the warm, dense environments of newly formed low-mass…