English
Related papers

Related papers: The evolution of Ap stars

200 papers

Magnetic A stars represent about $5\%$ of the upper main sequence stars and exhibit highly ordered, very stable and often very strong magnetic fields. They frequently show both, brightness- and spectral line profile variations synchronised…

Solar and Stellar Astrophysics · Physics 2014-02-19 Theresa Lueftinger

About 10% of hot stars host a fossil magnetic field on the pre-main sequence and main sequence. However, the first magnetic evolved hot stars have been discovered only recently. An observing program has been set up to find more such…

Solar and Stellar Astrophysics · Physics 2018-11-14 C. Neiner , A. Martin , G. Wade , M. Oksala

Rotation has a number of important effects on the evolution of stars. It decreases the surface gravity, causes enhanced mass loss and leads to surface abundance anomalies of various chemical isotopes. We have adapted the Cambridge stellar…

Solar and Stellar Astrophysics · Physics 2012-05-31 Adrian T. Potter

About 5% of upper main sequence stars are permeated by a strong magnetic field, the origin of which is still matter of debate. With this work we provide observational material to study how magnetic fields change with the evolution of stars…

Astrophysics · Physics 2009-11-11 S. Bagnulo , J. D. Landstreet , E. Mason , V. Andretta , J. Silaj , G. A. Wade

While magnetic fields have long been considered to be important for the evolution of magnetic non-degenerate stars and compact stars, it has become clear in recent years that actually all of the stars are deeply affected. This is…

Solar and Stellar Astrophysics · Physics 2021-02-03 Koh Takahashi , Norbert Langer

An arbitrary initial magnetic field in an A star evolves into a stable equilibrium. Simulations are presented of the formation of non-axisymmetric equilibria consisting of twisted flux tubes meandering under the surface of the star, and…

Astrophysics · Physics 2008-01-31 Jonathan Braithwaite

We are carrying out a survey of magnetic fields in Ap stars in open clusters in order to obtain the first sample of magnetic upper main sequence stars with precisely known ages. These data will constrain theories of field evolution in these…

Whereas the understanding of most phases of stellar evolution made considerable progress throughout the whole of the twentieth century, stellar formation remained rather enigmatic and poorly constrained by observations until about three…

Astrophysics · Physics 2015-05-13 J. F. Donati , M. M. Jardine , S. G. Gregory , J. Bouvier , C. Dougados , F. Menard

Observational data on rotation of Ap stars suggest that the bulk of their rotation rates form a separate Maxwellian distribution with an average value 3-4 times lower than the normal star distribution. No evidences for a significant angular…

Astrophysics · Physics 2007-05-23 K. Stepien

We present our view of the main physical ingredients determining the evolution of neutron star magnetic fields. This includes the basic properties of neutron star matter, possible scenarios for the origin of the magnetic field, constraints…

Astrophysics · Physics 2009-11-10 Andreas Reisenegger , Joaquin Prieto , Rafael Benguria , Dong Lai , Pablo Araya

The evolution of the magnetic field in an accreting neutron star is investigated using a fully general relativistic treatment and assuming that initially the currents supporting the field are completely confined to the crust. We find that…

Astrophysics · Physics 2009-10-31 Sushan Konar

During stellar evolution, especially in the PMS, stellar structure and rotation evolve significantly causing major changes in the dynamics and global flows of the star. We wish to assess the consequences of these changes on stellar dynamo,…

Solar and Stellar Astrophysics · Physics 2017-09-15 Constance Emeriau-Viard , Allan Sacha Brun

We review the current state of knowledge of magnetic fields inside stars, concentrating on recent developments concerning magnetic fields in stably stratified (zones of) stars, leaving out convective dynamo theories and observations of…

Solar and Stellar Astrophysics · Physics 2017-04-11 J. Braithwaite , H. C. Spruit

Until recently, the detection of magnetic fields at the surface of intermediate-mass main-sequence stars has been limited to Ap/Bp stars, a class of chemically peculiar stars. This class represents no more than 5-10% of the stars in this…

Solar and Stellar Astrophysics · Physics 2015-06-18 F. Lignières , P. Petit , M. Aurière , G. A. Wade , T. Böhm

Recent observational and theoretical results emphasize the potential significance of magnetic fields for structure, evolution, and environment of massive stars. Depending on their spectral and photometric behavior, the upper main-sequence…

Solar and Stellar Astrophysics · Physics 2013-09-24 M. Schoeller , S. Hubrig , M. Briquet , I. Ilyin

A significant fraction of massive main-sequence stars show strong, large-scale magnetic fields. The origin of these fields, their lifetimes, and their role in shaping the characteristics and evolution of massive stars are currently not well…

Solar and Stellar Astrophysics · Physics 2016-08-03 L. Fossati , F. R. N. Schneider , N. Castro , N. Langer , S. Simon-Diaz , A. Mueller , A. de Koter , T. Morel , V. Petit , H. Sana , G. A. Wade

The magnetic chemically peculiar (mCP) stars of the upper main sequence exhibit strong, globally-organised magnetic fields which are inclined to the rotational axis and facilitate the development of surface abundance inhomogeneities…

Solar and Stellar Astrophysics · Physics 2017-05-03 Martin Netopil , Ernst Paunzen , Stefan Hümmerich , Klaus Bernhard

Mass loss and axial rotation are playing key roles in shaping the evolution of massive stars. They affect the tracks in the HR diagram, the lifetimes, the surface abundances, the hardness of the radiation field, the chemical yields, the…

Astrophysics · Physics 2009-11-13 Georges Meynet , Sylvia Ekstrom , Cyril Georgy , Andre Maeder , Raphael Hirschi

We summarize the present status of the predictions of massive star models for the evolution of their surface properties. After discussing luminosity, temperature and chemical composition, we focus on the question whether massive stars may…

Astrophysics · Physics 2007-05-23 Norbert Langer , Alexander Heger

Surface rotation rates of young solar-type stars display drastic changes at the end of the pre-main sequence through the early main sequence. This may trigger corresponding changes in the magnetic dynamos operating in these stars, which…

Solar and Stellar Astrophysics · Physics 2016-02-03 C. P. Folsom , P. Petit , J. Bouvier , J. Morin , A. Lèbre