English
Related papers

Related papers: Generating neutron-star magnetic fields: three dyn…

200 papers

The stability properties of newly born neutron stars, or proto--neutron stars, are considered. We take into account dissipative processes, such as neutrino transport and viscosity, in the presence of a magnetic field. In order to find the…

Astrophysics · Physics 2009-11-07 Juan A. Miralles , Jose A. Pons , V. Urpin

Ferrario & Wickramasinghe (2006) explored the hypothesis that the magnetic fields of neutron stars are of fossil origin. In this context, they predicted the field distribution of the progenitor OB stars, finding that 5 per cent of main…

Astrophysics · Physics 2009-06-23 V. Petit , G. A. Wade , L. Drissen , T. Montmerle

Magnetars are isolated young neutron stars characterized by the most intense magnetic fields known in the universe. The origin of their magnetic field is still a challenging question. In situ magnetic field amplification by dynamo action is…

High Energy Astrophysical Phenomena · Physics 2022-12-07 P. Barrère , J. Guilet , A. Reboul-Salze , R. Raynaud , H. -T. Janka

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

This paper suggests the idea that all neutron stars experienced at birth an ultrafast decay of their magnetic fields from their initial values to their current surface values. If the electromagnetic energy radiated during this field decay…

Astrophysics of Galaxies · Physics 2012-04-05 Ricardo Heras

Magnetic fields have been detected on stars across the H-R diagram and substellar objects either directly by their effect on the formation of spectral lines, or through the activity phenomena they power which can be observed across a large…

Solar and Stellar Astrophysics · Physics 2015-06-11 J. Morin

Magnetic fields play a role in almost all stages of stellar evolution. Most low-mass stars, including the Sun, show surface fields that are generated by dynamo processes in their convective envelopes. Intermediate-mass stars do not have…

Solar and Stellar Astrophysics · Physics 2016-01-26 D. Stello , M. Cantiello , J. Fuller , D. Huber , R. A. Garcia , T. R. Bedding , L. Bildsten , V. Silva Aguirre

The observed galactic magnetic fields may have a primordial origin. I briefly review the observations, their interpretation in terms of the dynamo theory, and the current limits on cosmological magnetic fields. Several possible mechanisms…

Astrophysics · Physics 2007-05-23 Kari Enqvist

The recent discovery of the "weak field, old magnetar", the soft gamma repeater SGR 0418+5729, whose dipole magnetic field is less than 7.5 \times 10^{12} G, has raised perplexing questions: How can the neutron star produce SGR-like bursts…

High Energy Astrophysical Phenomena · Physics 2015-05-30 S. Dall'Osso , J. Granot , T. Piran

The surface rotation rates of young solar-type stars decrease rapidly with age from the end of the pre-main sequence though the early main sequence. This suggests that there is also an important change in the dynamos operating in these…

Solar and Stellar Astrophysics · Physics 2015-06-17 C. P. Folsom , P. Petit , J. Bouvier , J. -F. Donati , J. Morin

We argue that the first stars may have spanned the conventional mass range rather than be identified with the Very Massive Objects (100-1000 solar masses) favoured by numerical simulations. Specifically, we find that magnetic field…

Astrophysics · Physics 2008-11-26 Joseph Silk , Mathieu Langer

A model of the ferromagnetic origin of magnetic fields of neutron stars is considered. In this model, the magnetic phase transition occurs inside the core of neutron stars soon after formation. However, owing to the high electrical…

Astrophysics · Physics 2009-10-31 M. Kutschera

A wealth of X-ray and radio observations has revealed in the past decade a growing diversity of neutron stars (NSs) with properties spanning orders of magnitude in magnetic field strength and ages, and with emission processes explained by a…

High Energy Astrophysical Phenomena · Physics 2016-03-01 Adam Rogers , Samar Safi-Harb

Are magnetic fields important in primordial star formation? Assuming that star formation occurs via an accretion disk that is turbulent, initially because of local gravitational instability, we calculate the disk structure for realistic…

Astrophysics · Physics 2009-11-10 Jonathan C. Tan , Eric G. Blackman

In order to address the generation of neutron star magnetic fields, with particular focus on the dichotomy between magnetars and radio pulsars, we consider the properties of dynamos as inferred from other astrophysical systems. With…

High Energy Astrophysical Phenomena · Physics 2022-02-23 Christopher J. White , Adam Burrows , Matthew S. B. Coleman , David Vartanyan

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

We have investigated the turbulent mean-field dynamo action in protoneutron stars that are subject to convective and neutron finger instabilities. While the first one develops mostly in the inner regions of the star, the second one is…

Astrophysics · Physics 2009-11-10 Alfio Bonanno , Luciano Rezzolla , Vadim Urpin

In [Gusakov et al.\ PRD, 96, 103012, (2017)], we proposed a self-consistent method to study the quasistationary evolution of the magnetic field in neutron-star cores. Here we apply it to calculate the instantaneous particle velocities and…

High Energy Astrophysical Phenomena · Physics 2018-08-13 D. D. Ofengeim , M. E. Gusakov

After Michel (1994) introduced a phenomenological picture of `rapid magnetization' of newly born neutron stars (NSs), Muslimov & Page (1995) suggested that the physical conditions accompanying the formation of a NS may result in the surface…

Astrophysics · Physics 2009-10-28 A. Muslimov , D. Page

During the life of isolated neutron stars (NSs) their magnetic field passes through a variety of evolutionary phases. Depending on its strength and structure and on the physical state of the NS (e.g. cooling, rotation), the field looks…

Astrophysics · Physics 2015-06-24 U. Geppert