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We report the first study of OH(1720 MHz) masers in the LMC in order to probe regions where supernova remnants interact with adjacent molecular clouds. Using the ATCA, we observed four sources in the LMC and detected a single OH(1720 MHz)…

Astrophysics · Physics 2007-05-23 D. A. Roberts , F. Yusef-Zadeh

We present the first 6.7 GHz methanol maser linear polarization map of the extended filamentary maser structure around the compact HII region W3(OH). The methanol masers show linear polarization up to 8 per cent and the polarization angles…

Astrophysics · Physics 2009-11-11 W. H. T. Vlemmings , L. Harvey-Smith , R. J. Cohen

MERLIN phase-referenced polarimetric observations towards the W51 complex were carried out in March 2006 in the Class II methanol maser transition at 6.668 GHz and three of the four excited OH maser hyperfine transitions at 6 GHz. Methanol…

Astrophysics of Galaxies · Physics 2015-06-04 Sandra Etoka , Malcolm D. Gray , Gary A. Fuller

K 3-35 is a planetary nebula (PN) where H2O maser emission has been detected, suggesting that it departed from the proto-PNe phase only some decades ago. Interferometric VLA observations of the OH 18 cm transitions in K~3-35 are…

Solar and Stellar Astrophysics · Physics 2011-02-11 Y. Gomez , D. Tafoya , G. Anglada , L. F. Miranda , J. M. Torrelles , N. A. Patel , R. Franco-Hernandez

We present high angular resolution observations of OH maser emission towards the high-mass star forming region IRAS 06056+2131. The observations were carried out using the UK radio interferometer array, Multi-Element Radio Linked…

Solar and Stellar Astrophysics · Physics 2021-01-19 Mohamed Said darwish , Anita M. S. Richards , Sandra Etoka , Khaled Edris , Somaya Saad , Mohamed Beheary , Gary Fullar

We present VLBA observations of the ground-state hydroxyl masers in W3(OH) at 0.02 km s-1 spectral resolution. Over 250 masers are detected, including 56 Zeeman pairs. Lineshapes are predominantly Gaussian or combinations of several…

Astrophysics · Physics 2008-11-26 Vincent L. Fish , Walter F. Brisken , Loránt O. Sjouwerman

We present results of spectral line observations of the ground state transitions of hydroxyl(OH) toward supernova remnant IC 443 carried out with the Green Bank Telescope. At a spatial resolution of 7.2 arcminutes we detect weak, extended…

We present VLBA observations of 1667 MHz OH maser emission from the massive star formation region G5.89-0.39. The observations were phase referenced allowing the absolute positions of the masers to be obtained. The 1667 MHz masers have…

Astrophysics · Physics 2008-11-26 D. P. Stark , W. M. Goss , E. Churchwell , V. L. Fish , I. M. Hoffman

OH masers at 1720 MHz have proven to be excellent indicators of interactions between supernova remnants and molecular clouds. Recent calculations suggest that the 6049 MHz OH maser line is excited for higher column densities than for the…

Astrophysics · Physics 2009-11-13 Korinne E. McDonnell , Alan E. Vaughan , Mark Wardle

MERLIN measurements of 1.6-GHz OH masers associated with Orion-BN/KL are presented, and the data are compared with data on other masers, molecular lines, compact radio continuum sources and infrared sources in the region. OH masers are…

Astrophysics · Physics 2009-11-11 R. J. Cohen , N. Gasipron , J. Meaburn , M. F. Graham

Surface magnetic fields are detected in less than $10\%$ of the massive O-type star population and even less frequently among `old' massive stars approaching the terminal-age main sequence (TAMS). It is unclear to what extent the rarity of…

Solar and Stellar Astrophysics · Physics 2025-09-19 James A. Barron , Gregg A. Wade , Gonzalo Holgado , Sergio Simón-Díaz

We have used the Australia Telescope Compact Array (ATCA) to make a sensitive (5-$\sigma$ $\simeq$ 100 mJy) search for maser emission from the 4765-MHz $^2\Pi_{1/2}$ F=1$\to$0 transition of OH. Fifty five star formation regions were…

Astrophysics · Physics 2009-11-07 R. Dodson , S. P. Ellingsen , M. A. Voronkov

We want to study the velocity and magnetic field morphology in the vicinity (<1000 AU) of a massive young stellar object (YSO), at very high spatial resolution (10-100 AU). We performed milli-arcsecond polarimetric observations of the…

Solar and Stellar Astrophysics · Physics 2015-11-04 A. Sanna , G. Surcis , L. Moscadelli , R. Cesaroni , C. Goddi , W. H. T. Vlemmings , A. Caratti o Garatti

We have made observations of the four hyperfine transitions of the 2Pi(3/2), J=3/2 ground state of OH at 1612, 1665, 1667 and 1720 MHz and the related 1.6-GHz continuum emission, towards NGC 6334 using the Australia Telescope Compact Array.…

Astrophysics · Physics 2009-10-31 K. J. Brooks , J. B. Whiteoak

We present a survey of OH maser emission towards a sample of high mass protostellar objects made using the Nancay and GBT telescopes.OH maser emission was detected towards 63 objects with 36 new detections. There are 56 star-forming regions…

Astrophysics · Physics 2009-11-13 K. A. Edris , G. A. Fuller , R. J . Cohen

We have observed the OH (1720 MHz) line in five galactic SNRs with the VLA to measure their magnetic field strengths using the Zeeman effect. We detected all 12 of the bright ($S_{\nu} > 200$ mJy) OH (1720 MHz) masers previously detected by…

Astrophysics · Physics 2009-10-31 C. L. Brogan , D. A. Frail , W. M. Goss , T. H. Troland

The first images of 6.7-GHz methanol masers in the massive star-forming regions DR21(OH) and DR21(OH)N are presented. By measuring the shapes, radial velocities and polarization properties of these masers it is possible to map out the…

Astrophysics · Physics 2009-11-13 L. Harvey-Smith , R. Soria-Ruiz , A. Duarte-Cabral , R. J. Cohen

We report on one of the highest sensitivity surveys for molecular lines in the frequency range 6.0 to 7.4 GHz conducted to date. The observations were done with the 305m Arecibo Telescope toward a sample of twelve intermediate/high-mass…

Astrophysics of Galaxies · Physics 2020-07-08 W. S. Tan , E. D. Araya , L. E. Lee , P. Hofner , S. Kurtz , H. Linz , L. Olmi

G34.26+0.15 is a region of high-mass star formation that contains a broad range of young stellar objects in different stages of evolution, including a hot molecular core, hyper-compact HII regions and a prototypical cometary ultra-compact…

Astrophysics of Galaxies · Physics 2023-08-16 W. S. Tan , E. D. Araya , C. Rigg , P. Hofner , S. Kurtz , H. Linz , V. Rosero

We use archival WISE and Spitzer photometry to derive optical line fluxes for a sample of distant quasars at z ~6. We find evidence for exceptionally high equivalent width [OIII] emission (rest-frame EW ~400 {\AA}) similar to that inferred…

Astrophysics of Galaxies · Physics 2022-07-18 Bomee Lee , Ranga-Ram Chary