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Related papers: Extragalactic Zeeman Detections in OH Megamasers

200 papers

We report magnetic field measurements spanning about 15 years of four massive ($7.5-15 M_\odot$) supergiant stars: $\alpha$ Per (HD\,20902, F5Iab), $\alpha$ Lep (HD\,36673A, F0Ib), $\eta$ Leo (HD\,87737, A0Ib) and 13 Mon (HD\,46300, A1Ib).…

Solar and Stellar Astrophysics · Physics 2025-07-02 Gregg Wade , Mary Oksala , Coralie Neiner , Etienne Boucher , James Barron

Magnetic field investigations of Sun-like stars, using Zeeman splitting of non-polarised spectra, in the optical and H-band have found significantly different magnetic field strengths for the same stars, the cause of which is currently…

Global magnetic fields of active solar-like stars are nowadays routinely detected with spectropolarimetric measurements and are mapped with Zeeman-Doppler imaging (ZDI). However, due to the cancellation of opposite field polarities,…

Solar and Stellar Astrophysics · Physics 2020-03-25 O. Kochukhov , T. Hackman , J. J. Lehtinen , A. Wehrhahn

We present Chandra snapshot observations for a sample of 7 sources selected from the Arecibo OH megamaser (OHM) survey at z~0.13-0.22 and with far-infrared luminosities in excess of 10^{11} L_sun. In contrast with the known H2O megamasers,…

Astrophysics · Physics 2009-11-13 C. Vignali , W. N. Brandt , A. Comastri , J. Darling

Although the role of magnetic fields in launching molecular outflows in massive YSOs has been convincingly demonstrated by theoretical arguments, observationally, the alignment of the magnetic field lines with the molecular outflows is…

Astrophysics of Galaxies · Physics 2022-02-02 G. Surcis , W. H. T. Vlemmings , H. J. van Langevelde , B. Hutawarakorn Kramer , A. Bartkiewicz

We present mid-infrared spectra and photometry from the Infrared Spectrograph on the Spitzer Space Telescope for 51 OH megamasers (OHMs), along with 15 galaxies confirmed to have no megamaser emission above L_OH = 10^2.3 L_sun. The majority…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Kyle W. Willett , Jeremy Darling , Henrik W. W. Spoon , Vassilis Charmandaris , Lee Armus

We study the polarization of the SiO maser emission in a representative sample of evolved stars in order to derive an estimate of the strength of the magnetic field, and thus determine the influence of this magnetic field on evolved stars.…

Astrophysics · Physics 2007-05-23 Fabrice Herpin , Alain Baudry , Clemens Thum , Dave Morris , Helmut Wiesemeyer

Our analysis of a VLBA 12-hour synthesis observation of the OH masers in a well-known star-forming region W49N has yielded valuable data that enables us to probe distributions of magnetic fields in both the maser columns and the intervening…

Astrophysics of Galaxies · Physics 2015-06-16 Avinash A. Deshpande , W. M. Goss , J. E. Mendoza-Torres

M dwarfs are known to generate the strongest magnetic fields among main-sequence stars with convective envelopes, but the link between the magnetic fields and underlying dynamo mechanisms, rotation, and activity still lacks a consistent…

Magnetic fields are an important ingredient to cool star physics, and there is great interest in measuring fields and their geometry in order to understand stellar dynamos and their influence on star formation and stellar evolution. During…

Solar and Stellar Astrophysics · Physics 2015-03-17 Ansgar Reiners

We present the serendipitous detection of the two main OH maser lines at 1667 and 1665 MHz associated with IRAS 10597+5926 at z = 0.19612 in the untargeted Apertif Wide-area Extragalactic Survey (AWES), and the subsequent measurement of the…

We present a second epoch of observations of the 44 GHz Class I methanol maser line toward the star forming region OMC-2. The observations were carried out with the Very Large Array, and constitute one of the first successful Zeeman effect…

Astrophysics of Galaxies · Physics 2015-06-11 E. Momjian , A. P. Sarma

Magnetic fields in cool stars can be investigated by measuring Zeeman line broadening and polarization in atomic and molecular lines. Similar to the Sun, these fields are complex and height-dependent. Many molecular lines dominating M-dwarf…

Solar and Stellar Astrophysics · Physics 2019-09-11 N. Afram , S. V. Berdyugina

In order to complete the knowledge of the magnetic field and of its influence during the transition from Asymptotic Giant Branch to Planetary Nebulae stages, we have undertaken a search for magnetic fields at the surface of Mira stars. We…

Solar and Stellar Astrophysics · Physics 2015-06-17 A. Lèbre , M. Aurière , N. Fabas , D. Gillet , F. Herpin , R. Konstantinova-Antova , P. Petit

We summarise the main results of recent work on the Lyman break galaxy population which takes advantage of newly commissioned instrumentation on the VLT and Keck telescopes to push the detection of these objects to new wavelengths and more…

An accurate polarization calibration is essential for a spectral data analysis and Zeeman splitting measurements. Two anomalies challenge our understanding of OH megamasers in IRAS 02524+2046: an unexplained 1667/1665 MHz flux-ratio…

Astrophysics of Galaxies · Physics 2026-04-08 L. G. Hou , X. Y. Gao , Tao Hong , J. L. Han

The galaxy-IGM part of the Lyman-break survey currently consists of measured redshifts for more than 1000 galaxies with redshift 1.5<z<3.5 along the sightlines to 25 background QSOs. One of the goals of the survey was to measure the…

Astrophysics · Physics 2009-11-11 Kurt L. Adelberger

To investigate statistically whether magnetic fields in massive stars are ubiquitous or appear in stars with specific spectral classification, certain ages, or in a special environment, we acquired 41 new spectropolarimetric observations…

This Letter reports on initial Expanded Very Large Array (EVLA) observations of the 6035 MHz masers in ON 1. The EVLA data are of good quality, lending confidence in the new receiver system. Nineteen maser features, including six Zeeman…

Astrophysics · Physics 2015-05-13 Vincent L. Fish

Magnetic fields have been detected in several hundred white dwarfs, with strengths ranging from a few kG to several hundred MG. Only a few of the known fields have a mean magnetic field modulus below about 1 MG. We are searching for new…

Solar and Stellar Astrophysics · Physics 2016-06-29 J. D. Landstreet , S. Bagnulo , A. Martin , G. Valyavin
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