English
Related papers

Related papers: Why are some A stars magnetic, while most are not?

200 papers

Stars interact with their planets through gravitation, radiation, and magnetic fields. I shall focus on the interactions between late-type stars with an outer convection zone and close-in planets, i.e., with an orbital semimajor axis…

Earth and Planetary Astrophysics · Physics 2014-08-27 A. F. Lanza

Stars with radiative envelopes, specifically the upper main sequence chemically peculiar (Ap) stars, were among the first objects outside our solar system for which surface magnetic fields have been detected. Currently magnetic Ap stars…

Solar and Stellar Astrophysics · Physics 2015-06-17 O. Kochukhov

Recent spectro-polarimetric observations of solar-type stars have shown the presence of photospheric magnetic fields with a predominant toroidal component. If the external field is assumed to be current-free it is impossible to explain…

Solar and Stellar Astrophysics · Physics 2016-12-21 Alfio Bonanno

Both observations and modelling of magnetic fields in the diffuse interstellar gas of spiral galaxies are well developed but the theory has been confronted with observations for only a handful of individual galaxies. There is now sufficient…

Astrophysics of Galaxies · Physics 2015-06-23 Cameron Van Eck , Jo-Anne Brown , Anvar Shukurov , Andrew Fletcher

Star formation is thought to be triggered by gravitational collapse of the dense cores of molecular clouds. Angular momentum conservation during the collapse results in the progressive increase of the centrifugal force, which eventually…

Earth and Planetary Astrophysics · Physics 2015-05-28 Raquel Salmeron

Magnetic fields on a range of scales play a large role in the ecosystems of galaxies, both in the galactic disk and in the extended layers of gas away from the plane. Observing magnetic field strength, structure and orientation is complex,…

Astrophysics of Galaxies · Physics 2015-05-27 Marijke Haverkorn , Volker Heesen

Context. The first magnetic fields in O- and B-type stars that do not belong to the Bp-star class, have been discovered. The cyclic UV wind-line variability, which has been observed in a significant fraction of early-type stars, is likely…

Solar and Stellar Astrophysics · Physics 2011-08-15 R. S. Schnerr , H. F. Henrichs , C. Neiner , E. Verdugo , J. de Jong , V. C. Geers , K. Wiersema , B. van Dalen , A. Tijani , B. Plaggenborg , K. L. J. Rygl

A substantial fraction of the known neutron stars resides in X-ray binaries -- systems in which one compact object accretes matter from a companion star. Neutron stars in X-ray binaries have magnetic fields among the highest found in the…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Mikhail Revnivtsev , Sandro Mereghetti

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

Our theoretical and numerical analysis have suggested that for low-mass main sequences stars (of the spectral classes from M5 to G0) rotating much faster than the Sun, the generated large-scale magnetic field is caused by the mean-field…

Solar and Stellar Astrophysics · Physics 2024-04-19 N. Kleeorin , I. Rogachevskii , N. Safiullin , R. Gershberg , S. Porshnev

Direct measurements of magnetic fields in low-mass stars of spectral class M have become available during the last years. This contribution summarizes the data available on direct magnetic measurements in M dwarfs from Zeeman analysis in…

Solar and Stellar Astrophysics · Physics 2009-11-13 Ansgar Reiners

Enormous progress has been made on observing stellar magnetism in stars from the main sequence through to compact objects. Recent data have thrown into sharper relief the vexed question of the origin of stellar magnetic fields, which…

Solar and Stellar Astrophysics · Physics 2015-06-24 Lilia Ferrario , Andrew Melatos , Jonathan Zrake

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 (hereafter SPB) stars, along with a small…

Solar and Stellar Astrophysics · Physics 2009-11-13 S. Hubrig , M. Briquet , P. De Cat , M. Schoeller , T. Morel , I. Ilyin

Magnetars are young and highly magnetized neutron stars which display a wide array of X-ray activity including short bursts, large outbursts, giant flares and quasi-periodic oscillations, often coupled with interesting timing behavior…

High Energy Astrophysical Phenomena · Physics 2017-08-30 Victoria M. Kaspi , Andrei Beloborodov

We performed a highly sensitive search for magnetic fields on a large set of HgMn stars. With the aid of a new polarimeter attached to the HARPS spectrometer at the ESO 3.6m-telescope, we obtained high-quality circular polarization spectra…

The presence of magnetic fields is an attractive hypothesis for shaping PNe. We report on observations of the central star of the two Planetary Nebulae NGC1360 and LSS1326. We performed spectroscopy on circularly polarized light with the…

Solar and Stellar Astrophysics · Physics 2015-05-27 F. Leone , M. J. Martinez Gonzalez , R. L. M. Corradi , G. Privitera , R. Manso Sainz

The interior of a neutron star is likely to be predominantly a mixture of superfluid neutrons and superconducting protons. This results in the quantisation of the star's magnetic field into an array of thin fluxtubes, producing a…

Solar and Stellar Astrophysics · Physics 2015-06-12 S. K. Lander

In massive stars, magnetic fields are thought to confine the outflowing radiatively-driven wind, resulting in X-ray emission that is harder, more variable and more efficient than that produced by instability-generated shocks in non-magnetic…

Astrophysics · Physics 2009-11-13 V. Petit , G. A. Wade , L. Drissen , T. Montmerle , E. Alecian

The MiMeS project demonstrated that a small fraction of massive stars (around 7%) presents large-scale, stable, generally dipolar magnetic fields at their surface. They are supposed to be fossil remnants of initial phases of stellar…

Solar and Stellar Astrophysics · Physics 2015-06-22 Constance Emeriau , Stéphane Mathis

We construct the stably stratified magnetized stars within the framework of general relativity. The effects of magnetic fields on the structure of the star and spacetime are treated as perturbations of non-magnetized stars. By assuming…

General Relativity and Quantum Cosmology · Physics 2019-04-19 Shijun Yoshida