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Context. The importance of the magnetic field in high-mass-star formation is not yet fully clear and there are still many open questions concerning its role in the accretion processes and generation of jets and outflows. In the past few…

Solar and Stellar Astrophysics · Physics 2017-11-29 D. Dall'Olio , W. H. T. Vlemmings , G. Surcis , H. Beuther , B. Lankhaar , M. V. Persson , A. M. S. Richards , E. Varenius

We report new CO observations and a detailed molecular-line study of the mixed morphology (MM) supernova remnant (SNR) G359.1-0.5, which contains six OH (1720 MHz) masers along the radio shell, indicative of shock-cloud interaction.…

Astrophysics of Galaxies · Physics 2020-02-26 L. K. Eppens , E. M. Reynoso , J. Lazendic-Galloway , J. A. Combi , J. F. Albacete Colombo , -

We present first results of the H_2O Southern Galactic Plane Survey (HOPS), using the Mopra radiotelescope with a broad band backend and a beam size of about 2'. We have observed 100 square degrees of the southern Galactic plane at 12mm…

OH (1720 MHz) masers serve as indicators of SNR - molecular cloud interaction sites. These masers are collisionally excited in warm (50-100K) shocked gas with densities of order 1e5 cm^-3 when the OH column density is in the range 1e16-1e17…

Astrophysics · Physics 2009-11-13 Mark Wardle

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

We present the results of an interferometric study of 38 millimeter-wave lines of CH3OH in the region around the water maser source W3(H2O) and a region extending about 30" to the south and west of the hydroxyl maser source W3(OH). The…

We present the results of GBT observations of all four ground-state hydroxyl (OH) transitions toward 15 supernova remnants (SNRs) which show OH(1720 MHz) maser emission. This species of maser is well established as an excellent tracer of an…

Astrophysics · Physics 2009-11-13 J. W. Hewitt , F. Yusef-Zadeh , M. Wardle

We determine abundances from the absorption spectrum of the magnetic Herbig Ae star HD 190073 (V1295 Aql). The observations are primarily from HARPS spectra obtained at a single epoch. We accept arguments that the presence of numerous…

Solar and Stellar Astrophysics · Physics 2015-06-03 C. R. Cowley , S. Hubrig

We interpret the correlation between local star-forming galaxy positions and ultra-high-energy cosmic ray (UHECR) directions, recently detected by the Pierre Auger Observatory (PAO), in terms of physical parameters: the local density of…

High Energy Astrophysical Phenomena · Physics 2021-12-07 Arjen van Vliet , Andrea Palladino , Andrew Taylor , Walter Winter

A small subset of Galactic O-stars possess surface magnetic fields that alter the outflowing stellar wind by magnetically confining it. Key to the magnetic confinement is that it induces rotational modulation of spectral lines over the full…

Solar and Stellar Astrophysics · Physics 2021-06-23 Florian A. Driessen , Jon O. Sundqvist , Gregg A. Wade

Helium-rich hot subdwarf stars of spectral type O (He-sdO) are considered prime candidates for stellar merger remnants. Such events should lead to the generation of strong magnetic fields. However, no magnetic He-sdO has yet been…

Solar and Stellar Astrophysics · Physics 2022-02-09 M. Dorsch , N. Reindl , I. Pelisoli , U. Heber , S. Geier , A. G. Istrate , S. Justham

Maser lines from different molecular species, including water, hydroxyl, and methanol, are common observational phenomena associated with massive star forming regions. In particular, the methanol maser appears as an ideal tool to study the…

Astrophysics of Galaxies · Physics 2014-06-04 L. Olmi , E. D. Araya , P. Hofner , S. Molinari , J. Morales Ortiz , L. Moscadelli , M. Pestalozzi

Circumstellar OH maser lines are useful for studying the dynamics of the circumstellar envelope (CSE) around evolved stars. This study aims to identify CSEs around cold stars, which exhibit deviations from the spherical expansion, by…

Solar and Stellar Astrophysics · Physics 2024-12-03 Jia-Yong Xie , Jun-ichi Nakashima , Yong Zhang

Recently, a relationship between the water maser detection rate and far infrared (FIR) flux densities has been established as a result of two 22 GHz maser surveys in a complete sample of galaxies (Dec>-30 degree) with 100 micron flux…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 G. Surcis , A. Tarchi , C. Henkel , J. Ott , J. Lovell , P. Castangia

We present 92cm observations of the high-redshift galaxy B2 0902+343 (z=3.40) with the Westerbork Synthesis Radio Telescope (WSRT). Twenty-one cm HI is detected in absorption, at a depth of 15.9 mJy (=~6\sigma) and rest frame velocity width…

Astrophysics · Physics 2009-11-07 Ann Marie Cody , Robert Braun

Star formation is underway in the W49N molecular cloud (MC) at a high level of efficiency, with almost twenty ultra-compact (UC) HII regions observed thus far, indicating a recent formation of massive stars. Previous works have suggested…

Astrophysics of Galaxies · Physics 2023-09-19 Mendoza-Torres , J. E. , Juárez-Gama , M. , Rodríguez-Esnard , I. T

Neutral atomic hydrogen and molecular gas in the host galaxies of radio active galactic nuclei (AGN) can be traced using H I 21-cm and OH-1667 MHz absorption lines to understand the fueling and feedback processes. We present the results of…

Astrophysics of Galaxies · Physics 2024-07-01 Yogesh Chandola , D. J. Saikia , Yin-Zhe Ma , Zheng Zheng , Chao-Wei Tsai , Di Li , Denis Tramonte , Hengxing Pan

We report on ALMA observations of polarized dust emission at 1.2 mm from NGC6334I, a source known for its significant flux outbursts. Between five months, our data show no substantial change in total intensity and a modest 8\% variation in…

The OH Megamaser emission in the merging galaxy Arp220 has been re-observed with the Multi-Element Radio Linked Interferometer Network (MERLIN) and the European VLBI Network (EVN). Imaging results of the OH line emission at the two nuclei…

Astrophysics of Galaxies · Physics 2023-06-28 W. A. Baan , J. N. H. S. Aditya , T. An , H-R. Klöckner

Recently, a relationship between the water maser detection rate and far infrared (FIR) flux density has been found as a result of a 22 GHz maser survey in a sample comprised of northern galaxies with 100 micron flux density > 50 Jy and a…

Astrophysics · Physics 2007-12-06 P. Castangia , A. Tarchi , C. Henkel , K. M. Menten