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Related papers: OH(1720 MHz) Masers at the Galactic Centre

200 papers

We present the first variability study of the 1720 MHz OH masers located in the Galactic Center. Most of these masers are associated with the interaction between the supernova remnant SgrAEast and the interstellar medium, but a few masers…

Astrophysics of Galaxies · Physics 2015-05-28 Y. M. Pihlström , L. O. Sjouwerman , R. A. Mesler

Context. Maser emission is a strong tool for studying high mass star forming regions and their evolutionary stages. OH masers in particular can trace the circumstellar material around protostars and determine their magnetic field strengths…

Astrophysics of Galaxies · Physics 2017-12-13 K. A. Edris , G. A. Fuller , S. Etoka , R. J. Cohen

OH(1720 MHz) masers are excellent signposts of interaction between supernova remnants(SNRs) and molecular clouds. Using the GBT and VLA we have surveyed 75 SNRs and six candidates for maser emission. Four new interacting SNRs are detected…

Astrophysics of Galaxies · Physics 2009-11-13 John W. Hewitt , Farhad Yusef-Zadeh

We present MERLIN observations of OH maser and radio continuum emission from the Ultra Luminous IR Galaxy Markarian 231. The 1665- and 1667-MHz transitions have a combined velocity extent of 720 km/s and show a similar position-velocity…

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 , .

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

OH(1720 MHz) masers are created by the interaction of supernova remnants with molecular clouds. These masers are pumped by collisions in warm, shocked molecular gas with OH column densities in the range 10^{16}--10^{17} cm^{-2}. Excitation…

Astrophysics of Galaxies · Physics 2015-06-04 Mark Wardle , Korinne McDonnell

Aims: We have observed the 6030 and 6035 MHz transitions of OH in high-mass star-forming regions to obtain magnetic field estimates in both maser emission and absorption. Methods: Observations were taken with the Effelsberg 100 m telescope.…

Astrophysics · Physics 2009-11-11 Vincent L. Fish , Mark J. Reid , Karl M. Menten , Thushara Pillai

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

We present molecular-line observations at millimetre, centimetre and infrared wavelengths of the region containing OH(1720 MHz) masers in the supernova remnant (SNR) G349.7+0.2, using the Australia Telescope (AT) Mopra antenna, the…

Astrophysics · Physics 2011-04-20 J. S. Lazendic , M. Wardle , J. B. Whiteoak , M. G. Burton , A. J. Green

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 report the detection of 1720 and 1612 MHz OH ground-state satellite line maser regions in the starburst galaxy NGC253. We find ten compact maser features all of which are located along the narrow ridge of bright radio continuum emission…

Astrophysics · Physics 2009-10-30 D. T. Frayer , E. R. Seaquist , D. A. Frail

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

The environs of three supernova remnants (SNR) with associated OH 1720 MHz masers, G349.7+0.2, CTB 37A and G16.7+0.1, have been surveyed in the CO J=1-0 transition with the 12 Meter Telescope of the NRAO, using the On-The-Fly technique.…

Astrophysics · Physics 2009-10-31 Estela M. Reynoso , Jeffrey G. Mangum

Supernova remnants expanding into adjacent molecular clouds are believed to be sites of cosmic ray acceleration and sources of energetic gamma-rays. Under certain environmental conditions, such interactions also give rise to unusual OH…

Astrophysics · Physics 2009-11-06 Z. Arzoumanian , F. Yusef-Zadeh , T. J. W. Lazio

We report on OH maser emission toward G336.644-0.695 (IRAS 16333-4807), which is a H2O maser-emitting Planetary Nebula (PN). We have detected 1612, 1667 and 1720 MHz OH masers at two epochs using the Australia Telescope Compact Array…

We present results on a search for 86.243 GHz SiO (J = 2 -- 1, v = 1) maser emission toward 67 OH/IR stars located near the Galactic Centre. We detected 32 spectral peaks, of which 28 correspond to SiO maser lines arising from the envelopes…

Astrophysics of Galaxies · Physics 2020-07-08 M. Messineo , L. O. Sjouwerman , H. J. Habing , A. Omont

The collisional pumping of OH masers in non-dissociative C-type shocks near supernova remnants is considered. The emergence of maser emission in OH lines is investigated for various shock parameters - the shock speed, the preshock gas…

Astrophysics of Galaxies · Physics 2020-10-19 A. V. Nesterenok

We report the first results from a survey for 1665, 1667, and 1720 MHz OH emission over a small region of the Outer Galaxy centered at $l \approx 105.0\deg , b \approx +1.0\deg$ . This sparse, high-sensitivity survey ($\Delta Ta \approx…

Astrophysics of Galaxies · Physics 2015-06-23 Ronald J. Allen , David E. Hogg , Philip D. Engelke

Context: OH masers trace diverse physical processes, from the expanding envelopes around evolved stars to star-forming regions or supernovae remnants. Aims: We identify the ground-state OH masers at 18cm wavelength in the area covered by…