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Related papers: Magnetic fields in Local Group dwarf irregulars

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We performed a high-sensitivity search for galaxy-scale magnetic fields by radio polarimetry at 10.45GHz and 4.85GHz with the Effelsberg 100m radio telescope, accompanied by Halpha imaging, for the two Local Group irregular galaxies IC10…

Astrophysics · Physics 2009-11-10 K. T. Chyzy , J. Knapik , D. J. Bomans , U. Klein , R. Beck , M. Soida , M. Urbanik

Observations of magnetic A, B and O stars show that the poloidal magnetic flux per unit mass has an upper bound of 10^-6.5 G cm^2/g. A similar upper bound is found for magnetic white dwarfs even though the highest magnetic field strengths…

Solar and Stellar Astrophysics · Physics 2015-06-17 Dayal T. Wickramasinghe , Christopher A. Tout , Lilia Ferrario

Magnetic fields are observed beyond the peripheries of optically detected galactic discs, while numerical models of their origin and the typical magnitudes are still absent. Previously, studies of galactic dynamo have avoided considering…

Astrophysics of Galaxies · Physics 2014-09-05 E. Mikhailov , A. Kasparova , D. Moss , R. Beck , D. Sokoloff , A. Zasov

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…

Galaxies are observed to host magnetic fields with a typical total strength of around 15microgauss. A coherent large-scale field constitutes up to a few microgauss of the total, while the rest is built from strong magnetic fluctuations over…

Astrophysics of Galaxies · Physics 2024-01-09 Maarit J. Korpi-Lagg , Mordecai-Mark Mac Low , Frederick A. Gent

New low-frequency 74 and 330 MHz observations of the Galactic center (GC) region reveal the presence of a large-scale ($6\arcdeg\times 2\arcdeg$) diffuse source of nonthermal synchrotron emission. A minimum energy analysis of this emission…

Astrophysics · Physics 2011-07-18 T. N. LaRosa , C. L. Brogan , S. N. Shore , T. J. Lazio , N. E. Kassim , M. E. Nord

Magnetic fields play a fundamental role for interior and atmospheric properties of M dwarfs and greatly influence terrestrial planets orbiting in the habitable zones of these low-mass stars. Determination of the strength and topology of…

Solar and Stellar Astrophysics · Physics 2020-12-23 Oleg Kochukhov

It is still unknown how magnetic field-generation mechanisms could operate in low-mass dwarf galaxies. Here, we present a detailed study of a nearby pure-disk dwarf galaxy NGC 2976. Unlike previously observed dwarf objects, this galaxy…

Astrophysics of Galaxies · Physics 2016-04-06 R. T. Drzazga , K. T. Chyży , G. H. Heald , D. Elstner , J. S. Gallagher

Total magnetic fields in spiral galaxies, as observed through their total synchrotron emission, are strongest (up to \simeq 30\mu G) in the spiral arms. The degree of radio polarization is low; the field in the arms must be mostly turbulent…

Astrophysics · Physics 2009-11-11 Rainer Beck

A significant fraction of white dwarfs possess a magnetic field with strengths ranging from a few kG up to about 1000 MG. However, the incidence of magnetism varies when the white dwarf population is broken down into different spectral…

Solar and Stellar Astrophysics · Physics 2020-10-14 Adela Kawka

Magnetic fields of the order of $\mu$-Gauss are observationally detected in galaxies and galaxy clusters, which can be (at least) in part originated by the amplification of much weaker primordial seed fields. These fields should be carried…

High Energy Astrophysical Phenomena · Physics 2018-11-27 Paramita Barai , Elisabete M. de Gouveia Dal Pino

M dwarfs are the most abundant stars in the Galaxy and exhibit diverse magnetic behaviours. Understanding their large-scale magnetic fields is essential to study stellar dynamos and assess the impact of magnetic activity on planetary…

The average strength of the total magnetic field in the Milky Way, derived from radio synchrotron data under the energy equipartition assumption, is 6\muG locally and \simeq 10\muG at 3 kpc Galactic radius. Optical and synchrotron…

Astrophysics · Physics 2009-11-10 Rainer Beck

Magnetic fields can play an important role in stellar evolution. Among white dwarfs, the most common stellar remnant, the fraction of magnetic systems is more than 20 per cent. The origin of magnetic fields in white dwarfs, which show…

Solar and Stellar Astrophysics · Physics 2022-04-27 Ingrid Pelisoli , M. Dorsch , U. Heber , B. Gänsicke , S. Geier , T. Kupfer , P. Németh , S. Scaringi , V. Schaffenroth

A dynamo mechanism driven by differential rotation when stars merge has been proposed to explain the presence of strong fields in certain classes of magnetic stars. In the case of the high field magnetic white dwarfs (HFMWDs), the site of…

Solar and Stellar Astrophysics · Physics 2018-05-16 Gordon P. Briggs , Lilia Ferrario , Christopher A. Tout , Dayal T. Wickramasinghe

(abridged) We investigate the possibility to recognize the magnetic field structures in nearby galaxies and to test the cosmological evolution of their large- and small-scale magnetic fields with the SKA and its precursors. We estimate the…

Cosmology and Nongalactic Astrophysics · Physics 2010-02-18 T. G. Arshakian , R. Stepanov , R. Beck , M. Krause , D. Sokoloff , P. Frick

Fluctuation dynamos are thought to play an essential role in magnetized galaxy evolution, saturating within $\sim0.01~$Gyr and thus potentially acting as seeds for large-scale dynamos. However, unambiguous observational confirmation of the…

Astrophysics of Galaxies · Physics 2021-01-20 Amit Seta , Luiz Felippe S. Rodrigues , Christoph Federrath , Christopher A. Hales

The detection of strong, large-scale magnetic fields at the surface of only the oldest population of white dwarfs might point towards a hidden internal magnetic field slowly rising to the surface. In addition, strong magnetic fields have…

Solar and Stellar Astrophysics · Physics 2026-04-15 Lukas Einramhof , Lisa Bugnet , Leila Magdalena Calcaferro , Lucas Barrault , Srijan Bharati Das

Radio synchrotron emission is a powerful tool to study the strength and structure of magnetic fields in galaxies. Unpolarized synchrotron emission traces isotropic turbulent fields which are strongest in spiral arms and bars (20-30 \mu G)…

Astrophysics of Galaxies · Physics 2016-01-11 Rainer Beck

With the operation of LOFAR, a great opportunity exists to shed light on a problemof some cosmological significance. Diffuse radio synchrotron emission not associated to any obvious discrete sources as well as Faraday rotation in clusters…

Astrophysics of Galaxies · Physics 2015-03-19 Uli Klein , P. Papaderos