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We use a modified pulsar current analysis to study magnetic field decay in radio pulsars. In our approach we analyse the flow, not along the spin period axis as has been performed in previous studies, but study the flow along the direction…

High Energy Astrophysical Phenomena · Physics 2014-09-30 A. P. Igoshev , S. B. Popov

We present a new analysis of the expected magnetospheric radio emission from extrasolar giant planets for a distance limited sample of the nearest known extrasolar planets. Using recent results on the correlation between stellar X-ray flux…

Astrophysics · Physics 2009-11-10 Ian R. Stevens

While brown dwarfs show similarities with stars in their early life, their spin evolution is much more akin to that of planets. We have used lightcurves from the K2 mission to measure new rotation periods for 18 young brown dwarfs in the…

Earth and Planetary Astrophysics · Physics 2018-06-27 Aleks Scholz , Keavin Moore , Ray Jayawardhana , Suzanne Aigrain , Dawn Peterson , Beate Stelzer

We consider the magnetic interaction of exoplanets orbiting M-dwarfs, calculating the expected Poynting flux carried upstream along Alfv\'{e}n wings to the central star. A region of emission analogous to the Io footprint observed in…

Earth and Planetary Astrophysics · Physics 2018-02-28 S. Turnpenney , J. D. Nichols , G. A. Wynn , M. R. Burleigh

We present calculations of the auroral radio powers expected from exoplanets with magnetospheres driven by an Earth-like magnetospheric interaction with the solar wind. Specifically, we compute the twin cell-vortical ionospheric flows,…

Earth and Planetary Astrophysics · Physics 2016-07-27 J. D. Nichols , S. E. Milan

Weak magnetic fields must have existed in the early Universe, as they were sourced by the cross product of electron density and temperature gradients through the Biermann-battery mechanism. In this paper we calculate the magnetic fields…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-15 Nanoom Lee , Yacine Ali-Haimoud

We constrain the formation rate of Galactic magnetars directly from observations. Combining spin-down rates, magnetic activity, and association with supernova remnants, we put a 2$\sigma$ limit on their Galactic formation rate at…

High Energy Astrophysical Phenomena · Physics 2019-05-29 Paz Beniamini , Kenta Hotokezaka , Alexander van der Horst , Chryssa Kouveliotou

Like the magnetised planets in our Solar System, magnetised exoplanets should emit strongly at radio wavelengths. Radio emission directly traces the planetary magnetic fields and radio detections can place constraints on the physical…

Earth and Planetary Astrophysics · Physics 2018-05-03 C. R. Lynch , Tara Murphy , E. Lenc , D. L. Kaplan

Stars more massive than $\sim 1.3$ M$_\odot$ are known to develop a convective core during the main-sequence: the dynamo process triggered by this convection could be the origin of a strong magnetic field inside the core of the star,…

Solar and Stellar Astrophysics · Physics 2021-01-20 L. Bugnet , V. Prat , S. Mathis , R. A. García , S. Mathur , K. Augustson , C. Neiner , M. J. Thompson

Magnetised exoplanets are expected to emit at radio frequencies analogously to the radio auroral emission of Earth and Jupiter. We predict the radio emission from V830 Tau b, the youngest (2 Myr) detected exoplanet to date. We model the…

Solar and Stellar Astrophysics · Physics 2017-06-07 A. A. Vidotto , J. -F. Donati

Magnetized exoplanets are expected to emit auroral cyclotron radiation in the radio regime due to the interactions between their magnetospheres, the interplanetary magnetic field, and the stellar wind. Prospective extrasolar auroral…

Earth and Planetary Astrophysics · Physics 2025-08-14 Asaf Kaya , Tansu Daylan

Detection of radio emission from Jupiter was identified quickly as being due to its planetary-scale magnetic field. Subsequent spacecraft investigations have revealed that many of the planets, and even some moons, either have or have had…

Earth and Planetary Astrophysics · Physics 2024-06-25 T. Joseph W. Lazio

The surface magnetic field strength of white dwarfs is observed to vary from very little to around 10^9 G. Here we examine the proposal that the strongest fields are generated by dynamo action during the common envelope phase of strongly…

Solar and Stellar Astrophysics · Physics 2009-12-12 Adrian T. Potter , Christopher A. Tout

This paper describes results of magnetic field measurements of white dwarfs carried out on the 6-m telescope for the last years. A magnetic field of about Be ~ 28 kG has been discovered in the degenerate star WD 1953-011. A rotational…

Astrophysics · Physics 2007-05-23 S. N. Fabrika , G. G. Valyavin , T. E. Burlakova , E. A. Barsukova , D. N. Monin

We wish to clarify whether strong magnetic fields can be effectively generated in typically low-mass dwarf galaxies and to assess the role of dwarf galaxies in the magnetization of the Universe. We performed a search for radio emission and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Krzysztof T. Chyzy , Marek Wezgowiec , Rainer Beck , Dominik J. Bomans

Weak magnetic fields have recently been detected in Vega and Sirius. Here, we explore the possibility that these fields are the remnants of some field inherited or created during or shortly after star formation and, unlike true fossil…

Solar and Stellar Astrophysics · Physics 2015-06-03 Jonathan Braithwaite , Matteo Cantiello

We present a population synthesis study of the observed properties of the magnetars, which allows for X-ray selection effects, investigating the hypothesis that they are drawn from a population of progenitors that are more massive than…

Astrophysics · Physics 2009-11-13 Lilia Ferrario , D. T. Wickramasinghe

Many magnetic white dwarfs exhibit a polarised spectrum that periodically varies as the star rotates because the magnetic field is not symmetric about the rotation axis. In this work, we report the discovery that while weakly magnetic white…

Solar and Stellar Astrophysics · Physics 2024-11-18 S. Bagnulo , J. D. Landstreet

We present the results of a new series of non-gray calculations of the atmospheres, spectra, colors, and evolution of extrasolar giant planets (EGPs) and brown dwarfs for effective temperatures below 1300 K. This theory encompasses most of…

We examine the effects of the engulfment of planets by giant stars on the evolution of late-type stars. We show that the rate at which dynamo-generated magnetic energy is being released exceeds 10% of the wind kinetic energy when the…

Astrophysics · Physics 2016-08-30 Mario Livio , Noam Soker