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Related papers: Investigation of magnetically sensitive FeH lines

200 papers

Magnetic fields likely play an important role in star formation, but the number of directly measured magnetic field strengths remains scarce. We observed the 38.3 and 38.5 GHz Class II methanol (CH$_3$OH) maser lines toward the high mass…

Astrophysics of Galaxies · Physics 2023-09-29 E. Momjian , A. P. Sarma

Magnetic fields pervade in the interstellar medium (ISM) and are believed to be important in the process of star formation, yet probing magnetic fields in star formation regions is challenging. We propose a new method to use Faraday…

Astrophysics of Galaxies · Physics 2018-06-27 M. Tahani , R. Plume , J. C. Brown , J. Kainulainen

This paper presents a theoretical investigation on the polarization and magnetic sensitivity of the near-ultraviolet (near-UV) solar spectral lines of Fe II between 250 and 278 nm. In recent years, UV spectropolarimetry has become key to…

Solar and Stellar Astrophysics · Physics 2023-05-17 David Afonso Delgado , Tanausú del Pino Alemán , Javier Trujillo Bueno

High resolution spectropolarimetric observations of the strongly magnetic, super-slowly rotating rapidly oscillating Ap star HD166473 are used to investigate the implications of the presence of a variable strong magnetic field on the…

Solar and Stellar Astrophysics · Physics 2020-10-07 S. P. Järvinen , S. Hubrig , G. Mathys , V. Khalack , I. Ilyin , H. Adigozalzade

We report the discovery of the Zeeman effect in the 44 GHz Class I methanol maser line. The observations were carried out with 22 antennas of the EVLA toward a star forming region in OMC-2. Based on our adopted Zeeman splitting factor of z…

Astrophysics of Galaxies · Physics 2015-05-27 A. P. Sarma , E. Momjian

The uncertainty about a possible correlation between strength and inclination of the magnetic field and the continuum intensity of the sunspot penumbral fine-structure has been removed by a detailed analysis of a spatially very high…

Solar and Stellar Astrophysics · Physics 2016-05-26 E. Wiehr

The origin of magnetic fields in intermediate-mass and high-mass stars is fundamentally a mystery. Clues toward solving this basic astrophysical problem can likely be found at the pre-main sequence (PMS) evolutionary stage. With this work,…

Astrophysics · Physics 2008-11-26 G. A. Wade , S. Bagnulo , D. Drouin , J. D. Landstreet , D. Monin

We report the first detection of the Zeeman effect in the 36 GHz Class I methanol maser line. The observations were carried out with 13 antennas of the EVLA toward the high mass star forming region M8E. Based on our adopted Zeeman splitting…

Astrophysics of Galaxies · Physics 2014-11-20 A. P. Sarma , E. Momjian

The bright A-type metallic-line star o Peg was reported in the early 1990s to have a surface magnetic field of ~2kG by analyzing the widths and strengths of spectral lines. In respect that those old studies were of rather empirical or…

Solar and Stellar Astrophysics · Physics 2023-05-03 Yoichi Takeda

Approximately 7% of massive stars host stable surface magnetic fields that are strong enough to alter stellar evolution through their effect on the stellar wind. It is therefore crucial to characterize the strength and structure of these…

Solar and Stellar Astrophysics · Physics 2021-07-20 C. Erba , V. Petit , K. Gayley , R. Ignace , A. ud-Doula , G. A. Wade

The Zeeman pattern of MnI lines is sensitive to hyperfine structure (HFS) and, they respond to hG magnetic field strengths differently from the lines used in solar magnetometry. This peculiarity has been employed to measure magnetic field…

Astrophysics · Physics 2009-11-13 J. Sanchez Almeida , B. Viticchie , E. Landi Degl'Innocenti , F. Berrilli

The measurement of Zeeman splitting in spectral lines---both in emission and absorption---can provide direct estimates of the magnetic field strength and direction in atomic and molecular clouds, both in our own Milky Way and in external…

The three Mn I lines at 17325, 17339 and 17349 \AA~are among the 25 strongest lines ($\log(gf)>0.5$) in the H-band. They are all heavily broadened due to hyperfine structure and the profiles of these lines have so far not been understood.…

Solar and Stellar Astrophysics · Physics 2015-06-19 Martin Andersson , Jon Grumer , Nils Ryde , Richard Blackwell-Whitehead , Roger Hutton , Yaming Zou , Per Jönsson , Tomas Brage

The polarized emission of astrophysical masers, especially OH and methanol lines, is an effective tool to study the magnetic field in high-mass star-forming regions. The magnetic field strength measurement via the Zeeman effect of OH maser…

Astrophysics of Galaxies · Physics 2025-08-21 A. Kobak , G. Surcis , A. Bartkiewicz , W. H. T. Vlemmings , M. Szymczak

The nearby M dwarf binary GJ65AB, also known as BL Cet and UV Cet, is a unique benchmark for investigation of dynamo-driven activity of low-mass stars. Magnetic activity of GJ65 was repeatedly assessed by indirect means, such as studies of…

Solar and Stellar Astrophysics · Physics 2017-02-13 O. Kochukhov , A. Lavail

Context. Investigations of the magnetism of the quiet Sun are hindered by extremely weak polarization signals in Fraunhofer spectral lines. Photon noise, straylight, and the systematically different sensitivity of the Zeeman effect to…

Almost three decades ago, Mathys (1990) demonstrated the importance of studying Ap stars showing resolved Zeeman split Fe II 6147.7 and 6149.2 lines. Such Zeeman split lines can be seen in stars whose projected rotational velocity is…

Solar and Stellar Astrophysics · Physics 2018-12-11 S. Hubrig , S. P. Jarvinen , M. Schöller , J. F. Gonzalez

This study based on longitudinal Zeeman effect magnetograms and spectral line scans investigates the dependence of solar surface magnetic fields on the spectral line used and the way the line is sampled in order to estimate the magnetic…

Astrophysics · Physics 2009-11-13 R. K. Ulrich , L. Bertello , J. E. Boyden , L. Webster

We aim at a highly sensitive search for weak magnetic fields in main sequence stars of intermediate mass, by scanning classes of stars with no previously reported magnetic members. After detecting a weak magnetic field on the normal,…

Solar and Stellar Astrophysics · Physics 2015-05-28 P. Petit , F. Lignières , M. Aurière , G. A. Wade , D. Alina , J. Ballot , T. Böhm , L. Jouve , A. Oza , F. Paletou , S. Théado

Stellar UV spectra are fundamental diagnostics of physical and magnetic properties of stars. For instance, lines like Mg II at 280 nm serve as valuable indicators of stellar activity, providing insights into the activity levels of Sun-like…