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Related papers: Protoneutron star dynamos and pulsar magnetism

200 papers

In their early stages, protoplanetary discs are sufficiently massive to undergo gravitational instability (GI). This instability is thought to be involved in mass accretion, planet formation via gas fragmentation, the generation of spiral…

Earth and Planetary Astrophysics · Physics 2021-06-30 A. Riols , W. Xu , G. Lesur , M. W. Kunz , H. Latter

Radial pulsations of newborn neutron stars (protoneutron stars) are studied for a range of internal temperatures and entropies per baryon predicted by the existing numerical simulations. Protoneutron star models are constructed using a…

Astrophysics · Physics 2008-11-26 D. Gondek , P. Haensel , J. L. Zdunik

Magnetic fields grow quickly even at early cosmological times, suggesting the action of a small-scale dynamo (SSD) in the interstellar medium of galaxies. Many studies have focused on idealized turbulent driving of the SSD. Here we simulate…

Astrophysics of Galaxies · Physics 2021-04-07 Frederick A. Gent , Mordecai-Mark Mac Low , Maarit J. Kapyla , Nishant K. Singh

Fast spinning neutron stars, recycled in low mass binaries, may have accreted a substantial amount of mass. The available relativistic measurements of neutron star masses, all clustering around 1.4 M_sun, however refer mostly to slowly…

Astrophysics · Physics 2009-10-31 Luciano Burderi , Andrea Possenti , Monica Colpi , Tiziana Di Salvo , Nichi D'Amico

We consider the amplification and transport of a magnetic field in the collapsed core of a massive star, including both the region between the neutrinosphere and the shock, and the central, opaque core. An analytical argument explains why…

Astrophysics · Physics 2009-11-06 Christopher Thompson , Norman Murray

By performing 2.5-dimensional general relativistic radiation magnetohydrodynamic simulations, we demonstrate supercritical accretion onto a non-rotating, magnetized neutron star, where the magnetic field strength of dipole fields is…

High Energy Astrophysical Phenomena · Physics 2017-08-23 Hiroyuki R. Takahashi , Ken Ohsuga

The surface rotation rates of young solar-type stars vary rapidly with age from the end of the pre-main sequence through the early main sequence. Important changes in the dynamos operating in these stars may result from this evolution,…

Solar and Stellar Astrophysics · Physics 2016-01-27 C. P. Folsom , P. Petit , J. Bouvier , A. Lèbre , L. Amard , A. Palacios , J. Morin , J. -F. Donati , S. V. Jeffers , S. C. Marsden , A. A. Vidotto

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

Recent asteroseismic analyses have revealed the presence of strong (B $\gtrsim 10^5$ G) magnetic fields in the cores of many red giant stars. Here, we examine the implications of these results for the evolution of stellar magnetic fields,…

Solar and Stellar Astrophysics · Physics 2016-06-15 Matteo Cantiello , Jim Fuller , Lars Bildsten

An update is given on the current status of solar and stellar dynamos. At present, it is still unclear why stellar cycle frequencies increase with rotation frequency in such a way that their ratio increases with stellar activity. The…

Solar and Stellar Astrophysics · Physics 2015-06-15 Axel Brandenburg

We present analytic calculations of the electromagnetic torques acting on a magnetic neutron star rotating in vacuum, including near-zone torques associated with the inertia of dipole and quadrupole magnetic fields. We incorporate these…

Solar and Stellar Astrophysics · Physics 2015-06-12 J. J. Zanazzi , Dong Lai

M dwarfs are the most numerous stars in our Galaxy with masses between approximately 0.5 and 0.1 solar mass. Many of them show surface activity qualitatively similar to our Sun and generate flares, high X-ray fluxes, and large-scale…

Solar and Stellar Astrophysics · Physics 2018-01-29 D. Shulyak A. Reiners , A. Engeln , L. Malo , R. Yadav , J. Morin , O. Kochukhov

We use numerical MHD to look at the stability of a possible poloidal field in neutron stars (Flowers & Ruderman 1977), and follow its unstable evolution, which leads to the complete decay of the field. We then model a neutron star after the…

Astrophysics · Physics 2009-11-11 J. Braithwaite , H. C. Spruit

There has recently been growing evidence for the existence of neutron stars possessing magnetic fields with strengths that exceed the quantum critical field strength of $4.4 \times 10^{13}$ G, at which the cyclotron energy equals the…

Astrophysics · Physics 2009-11-11 Alice K. Harding , Dong Lai

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

Stellar dynamos generate magnetic fields that are of fundamental importance to the variability and evolution of Sun-like and low-mass stars, and for the development of their planetary systems. We report measurements of surface-average…

The model that describes operation of dynamo in fully convective stars is presented. It is based on representation of stellar magnetic field as a superposition of finite number of poloidal and toroidal free damping modes. In the frame of…

Astrophysics · Physics 2009-11-13 D. D. Sokoloff , S. N. Nefedov , A. A. Ermash , S. A. Lamzin

Treatment of the vortex motion in the superfluids of the inner crust and the outer core of neutron stars is a key ingredient in modeling a number of pulsar phenomena, including glitches and magnetic field evolution. After recalculating the…

High Energy Astrophysical Phenomena · Physics 2016-08-17 Erbil Gügercinoğlu , M. Ali Alpar

In this paper we present calculations of period distribution for old accreting isolated neutron stars (INSs). At the age about a few billions years low velocity INSs come to the stage of accretion. At that stage their period evolution is…

Astrophysics · Physics 2007-05-23 S. B. Popov , M. E. Prokhorov , A. V. Khoperskov , V. M. Lipunov

We study the evolution of the field on the surface of proto-neutron stars in the immediate aftermath of stellar core collapse by analyzing the results of self-consistent, axisymmetric simulations of the cores of rapidly rotating high-mass…

High Energy Astrophysical Phenomena · Physics 2018-01-17 Martin Obergaulinger , Miguel-Ángel Aloy