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Related papers: Geomagnetic spikes on the core-mantle boundary

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The magnetopause marks the outer edge of the Earth's magnetosphere and a distinct boundary between solar wind and magnetospheric plasma populations. In this letter, we use global magnetohydrodynamic simulations to examine the response of…

The origin of cosmic magnetic fields is an unsolved problem and magnetogenesis could have occurred in the early Universe. We study the evolution of such primordial magnetic fields across the cosmological recombination epoch via 3D…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-25 Pranjal Trivedi , Johannes Reppin , Jens Chluba , Robi Banerjee

Context. The Sun shows an activity cycle that is caused by its varying global magnetic field. During a solar cycle, sunspots, i.e. extended regions of strong magnetic fields, occur in activity belts that are slowly migrating from middle to…

Solar and Stellar Astrophysics · Physics 2015-11-25 D. Utz , R. Muller , S. Thonhofer , A. Veronig , A. Hanslmeier , M. Bodnárová , M. Bárta , J. C. del Toro Iniesta

We present magnetohydrodynamic (MHD) simulations of the atmospheres of hot Jupiters ranging in temperature from 1100-1800K. Magnetic effects are negligible in atmospheres with temperatures $\lesssim$ 1400K. At higher temperatures winds are…

Earth and Planetary Astrophysics · Physics 2015-06-22 Tamara M. Rogers , Thaddeus D. Komacek

The experimental data on GOES magnetic measurements and plasma measurements on LANL geosynchronous satellites is used for selection of 169 case events containing 638 geosynchronous magnetopause crossings (GMCs) in 1995 to 2001. We study the…

Earth and Planetary Astrophysics · Physics 2011-10-25 A. Suvorova , A. Dmitriev , J. -K. Chao , M. Thomsen , Y. -H. Yang

In this paper, we study analytically the process of external generation and subsequent free evolution of the lepton chiral asymmetry and helical magnetic fields in the early hot universe. This process is known to be affected by the Abelian…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-18 Maksym Sydorenko , Oleksandr Tomalak , Yuri Shtanov

We test the ability of large scale velocity fields inferred from geomagnetic secular variation data to produce the global magnetic field of the Earth.Our kinematic dynamo calculations use quasi-geostrophic (QG) flows inverted from…

Geophysics · Physics 2016-01-20 Nathanaël Schaeffer , Estelina Lora Silva , Maria Alexandra Pais

Using recent data obtained by Advanced Composition Explorer (ACE) the pumping scale of the magnetic field gradients of the solar wind plasma has been calculated. This pumping scale is found to be equal to 24h $\pm$ 2h. The ACE spacecraft…

Chaotic Dynamics · Physics 2007-05-23 A. Bershadskii

We demonstrate that the radial magnetic-field component at the outer boundary of the sunspot penumbra is about 550 Mx cm$^{-2}$ independent of the sunspot area and the maximum magnetic field in the umbra. The mean magnetic-field intensity…

Solar and Stellar Astrophysics · Physics 2022-10-26 V. N. Obridko , M. M. Katsova , D. D. Sokoloff , B. D. Shelting , I. M. Livshits

A peak has been unambiguously detected in the cosmic microwave background (CMB) angular spectrum. Here we characterize its properties with fits to phenomenological models. We find that the TOCO and BOOM/NA data determine the peak location…

Astrophysics · Physics 2009-10-31 Lloyd Knox , Lyman Page

We discuss the generation of large-scale magnetic fields due to the breaking of the conformal invariance in the electromagnetic field through the $CPT$-even dimension-six Chern-Simons-like effective interaction with a fermion current in…

Astrophysics · Physics 2008-12-18 K. Bamba , C. Q. Geng , S. H. Ho

The universe is magnetized on all scales probed so far. On the largest scales, galaxies and galaxy clusters host magnetic fields at the micro Gauss level coherent on scales up to ten kpc. Recent observational evidence suggests that even the…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-26 Kandaswamy Subramanian

We present the first constraints on primordial magnetic fields from the Lyman-$\alpha$ forest using full cosmological hydrodynamic simulations. At the scales and redshifts probed by the data, the flux power spectrum is extremely sensitive…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-29 Mak Pavičević , Vid Iršič , Matteo Viel , James Bolton , Martin G. Haehnelt , Sergio Martin-Alvarez , Ewald Puchwein , Pranjal Ralegankar

We present results of three-dimensional MHD simulations of recurrent eruptions in emerging flux regions. The initial numerical setup is the same with the work by Syntelis et al. 2017 (hereafter, Paper I). Here, we perform a parametric study…

Solar and Stellar Astrophysics · Physics 2019-05-15 P. Syntelis , V. Archontis , K. Tsinganos

Intergalactic magnetic fields are assumed to have been spontaneously generated at the reheating stage of the early Universe, due to vacuum polarization of non-Abelian gauge fields at high temperature. The fact that the screening mass of…

High Energy Physics - Phenomenology · Physics 2015-06-04 E. Elizalde , V. Skalozub

Geomagnetic field variations during five major Solar Energetic Particle (SEP) events of solar cycle 23 have been investigated in the present study. The SEP events of 01 oct 2001, 04 Nov 2001, 21 Apr 2002 and 14 May 2005 have been selected…

Earth and Planetary Astrophysics · Physics 2015-06-17 Parvaiz A. Khan , Sharad C. Tripathi , O. A. Troshichev , Malik A. Waheed , Aslam A. M. , A. K. Gwal

An X1.7 flare at 10:15 UT and a halo CME with a projected speed of 942 km/s erupted from NOAA solar active region 9393 located at N20W19, were observed on 2001 March 29. When the CME reached the Earth, it triggered a super geomagnetic storm…

Space Physics · Physics 2020-03-09 Li-Bin Cheng , Gui-Ming Le , Ming-Xian Zhao

Generation of cosmic microwave background (CMB) elliptic polarization due to the Cotton-Mouton (CM) effect in a cosmic magnetic field is studied. We concentrate on the generation of CMB circular polarization and on the rotation angle of the…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-19 Damian Ejlli

We present a theoretical study of CMB temperature peaks, including its effect over the polarization field, and allowing nonzero eccentricity. The formalism is developed in harmonic space and using the covariant derivative on the sphere,…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-25 A. Marcos-Caballero , R. Fernández-Cobos , E. Martínez-González , P. Vielva

The generation of large-scale magnetic fields is studied in dilaton electromagnetism in inflationary cosmology, taking into account the dilaton's evolution throughout inflation and reheating until it is stabilized with possible entropy…

Astrophysics · Physics 2008-11-26 Kazuharu Bamba , J. Yokoyama