English
Related papers

Related papers: Are there tangled magnetic fields on HgMn stars?

200 papers

We report on the detection of a strong, organized magnetic field in the helium-variable early B-type star HR 7355 using spectropolarimetric data obtained with ESPaDOnS on CFHT by the MiMeS large program. We also present results from new…

Solar and Stellar Astrophysics · Physics 2015-05-20 M. E. Oksala , G. A. Wade , W. L. F. Marcolino , J. Grunhut , D. A. Bohlender , N. Manset , R. H. D. Townsend , the MiMeS Collaboration

Our understanding of magnetic fields in late-type stars is strongly driven by what we know of the solar magnetic field. For this reason, it is crucial to understand how typical the solar dynamo is. To do this we need to compare the solar…

Solar and Stellar Astrophysics · Physics 2016-05-13 L. Fossati , O. Kochukhov , J. S. Jenkins , R. J. Stancliffe , C. A. Haswell , A. Elmasli , E. Nickson

The magnetic field in the O9.7 V star HD54879 has been monitored for almost a decade. Spectropolarimetric observations reveal a rather strong mean longitudinal magnetic field that varies with a period of about 7.41 yr. Observations in the…

Solar and Stellar Astrophysics · Physics 2024-03-01 Manfred Küker , Silva Järvinen , Swetlana Hubrig , Ilya Ilyin , Markus Schöller

We have carried out a study of radio emission from a small sample of magnetic O- and B-type stars using the Giant Metrewave Radio Telescope, with the goal of investigating their magnetospheres at low frequencies. These are the lowest…

Solar and Stellar Astrophysics · Physics 2015-08-06 P. Chandra , G. A. Wade , J. O. Sundqvist , D. Oberoi , J. H. Grunhut , A. ud-Doula , V. Petit , D. H. Cohen , M. E. Oksala , A. David-Uraz

We present here the first results of a spectropolarimetric analysis of a small sample (about 20) of active stars ranging from spectral type M0 to M8, which are either fully-convective or possess a very small radiative core. This study aims…

Astrophysics · Physics 2014-11-18 J. Morin , J. -F. Donati , X. Delfosse , T. Forveille , M. M. Jardine

The upper main sequence magnetic chemically peculiar (Ap) stars exhibit a non-uniform distribution of chemical elements across their surfaces and with height in their atmospheres. These inhomogeneities, responsible for the conspicuous…

Solar and Stellar Astrophysics · Physics 2015-05-20 Oleg Kochukhov

The B2Vn star HR 7355 is found to be a He-rich magnetic star. Spectropolarimetric data were obtained with FORS1 at UT2 on Paranal observatory to measure the disk-averaged longitudinal magnetic field at various phases of the presumed 0.52 d…

Solar and Stellar Astrophysics · Physics 2015-05-18 Th. Rivinius , Th. Szeifert , L. Barrera , R. H. D. Townsend , S. Stefl , D. Baade

We report the discovery of a new magnetic DA white dwarf (WD), WD0011-721, which is located within the very important 20pc volume-limited sample of the closest WDs to the Sun. This star has a mean field modulus <|B|> of 343 kG, and from the…

Solar and Stellar Astrophysics · Physics 2019-08-07 John D. Landstreet , Stefano Bagnulo

To determine the frequencies of magnetic oscillations in neutron stars with highly tangled magnetic fields, we derive the perturbation equations. We assume that the field strength of the global magnetic structure is so small that such…

High Energy Astrophysical Phenomena · Physics 2015-11-18 Hajime Sotani

Hot cluster Horizontal Branch (HB) stars and field subdwarf B (sdB) stars are core helium burning stars that exhibit abundance anomalies that are believed to be due to atomic diffusion. Diffusion can be effective in these stars because they…

Solar and Stellar Astrophysics · Physics 2015-06-03 G. Mathys , S. Hubrig , E. Mason , G. Michaud , M. Schoeller , F. Wesemael

Strong magnetic fields are observed in a substantial fraction of upper main sequence stars and white dwarfs. Many such stars are observed to exhibit photometric modulations as the magnetic poles rotate in and out of view, which could be a…

Solar and Stellar Astrophysics · Physics 2023-02-22 Jim Fuller , Stephane Mathis

Our knowledge of the magnetism in white dwarfs is based on an observational dataset that is biased in favour of stars with very strong magnetic fields. Most of the field measurements available in the literature have a relatively low…

Solar and Stellar Astrophysics · Physics 2018-10-24 Stefano Bagnulo , John D. Landstreet

The Magnetism in Massive Stars (MiMeS) survey represents a high precision systematic search for magnetic fields in hot, massive OB stars. To date, MiMeS Large Programs (ESPaDOnS@CFHT, Narval@TBL, [email protected]) and associated PI programs…

Solar and Stellar Astrophysics · Physics 2012-06-26 G. A. Wade , J. H. Grunhut , the MiMeS Collaboration

The presence of magnetic fields in O-type stars has been suspected for a long time. The discovery of such fields would explain a wide range of well documented enigmatic phenomena in massive stars, in particular cyclical wind variability,…

Solar and Stellar Astrophysics · Physics 2009-11-13 S. Hubrig , M. Schoeller , R. S. Schnerr , I. Ilyin , H. F. Henrichs , R. Ignace , J. F. Gonzalez

For early type magnetic stars slow, at most moderate rotational velocities have been considered an observational fact. The detection of a multi-kilogauss magnetic field in the B2Vpn star with P approx. 0.52d and v sin approx. 300km/s has…

Solar and Stellar Astrophysics · Physics 2015-05-20 Th. Rivinius , R. H. D. Townsend , S. Štefl , D. Baade

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

gam Peg is a bright B pulsator showing both p and g modes of beta Cep and SPB types. It has also been claimed to be a magnetic star by some authors while others do not detect a magnetic field. We aimed at checking for the presence of a…

Solar and Stellar Astrophysics · Physics 2015-06-18 C. Neiner , D. Monin , B. Leroy , S. Mathis , D. Bohlender

We report on a detailed abundance study of six bright, mostly southern, slowly rotating late B stars: HD~1279 (B8III), HD~99803 (B9V), HD~123445 (B9V), HD~147550 (B9V), HD~171961 (B8III) and HD~202671 (B5II/III), hitherto reported as normal…

We present the results of the continuation of our magnetic survey with FORS1 at the VLT of a sample of B-type stars consisting of confirmed or candidate beta Cephei stars and Slowly Pulsating B stars. Roughly one third of the studied beta…

Solar and Stellar Astrophysics · Physics 2009-01-22 S. Hubrig , M. Briquet , P. De Cat , M. Schoeller , T. Morel , I. Ilyin

Weak magnetic fields have recently been detected in a number of A-type stars, including Vega and Sirius. At the same time, space photometry observations of A- and late B-type stars from Kepler and TESS have highlighted the existence of…

Solar and Stellar Astrophysics · Physics 2019-10-02 Matteo Cantiello , Jonathan Braithwaite