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Related papers: Realization of Bullard's disc dynamo

200 papers

We use polarization observations of a circumbinary disk to investigate how the polarization properties change at distinct frequency bands. Our goal is to discern the main mechanism responsible for the polarization through comparison between…

A series of numerical simulations of the dynamo process operating inside gas giant planets has been performed. We use an anelastic, fully nonlinear, three-dimensional, benchmarked MHD code to evolve the flow, entropy and magnetic field. Our…

Earth and Planetary Astrophysics · Physics 2018-01-11 Wieland Dietrich , Chris. A. Jones

We present the structure of the 3D ideal MHD pulsar magnetosphere to a radius ten times that of the light cylinder, a distance about an order of magnitude larger than any previous such numerical treatment. Its overall structure exhibits a…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Constantinos Kalapotharakos , Ioannis Contopoulos , Demos Kazanas

We report the results of three-dimensional numerical simulations of convection-driven dynamos in relatively thin rotating spherical shells that show a transition from an strong non-oscillatory dipolar magnetic field to a weaker regularly…

Fluid Dynamics · Physics 2011-02-08 R. D. Simitev , F. H. Busse , A. G. Kosovichev

Cellular traction forces are conventionally measured by tracking the displacement of beads or micropillars, an approach fundamentally limited by optical diffraction and the classical Euler-Bernoulli beam assumption, which is accurate only…

Optics · Physics 2026-03-09 Linjie Ma , Bicong Wang , Tai Nam Yip , Yong Hou , Yuan Lin , Zhiqin Chu

The degree of intermittency of the magnetic field of a large-scale dynamo is considered. Based on simulations it is argued that there is a tendency for the field to become more diffuse and non-intermittent as the dynamo saturates. The…

Solar and Stellar Astrophysics · Physics 2011-07-14 Axel Brandenburg

We perform MHD simulations of a thin resistive and viscous accretion disk around a neutron star with the surface dipolar magnetic field of 10$^8$ Gauss. The system evolution is followed during the interval of 500 millisecond pulsar…

High Energy Astrophysical Phenomena · Physics 2018-02-02 M. Čemeljić , V. Parthasarathy , W. Kluźniak

Inertial sensors that measure the acceleration of ultracold atoms promise unrivalled accuracy compared to classical equivalents. However, atomic systems are sensitive to various perturbations, including magnetic fields, which can introduce…

Atomic Physics · Physics 2023-12-11 A. Davis , P. J. Hobson , T. X. Smith , C. Morley , H. G. Sewell , J. Cotter , T. M. Fromhold

The Hofstadter-Hubbard model captures the physics of strongly correlated electrons in an applied magnetic field, which is relevant to many recent experiments on Moir\'e materials. Few large-scale, numerically exact simulations exists for…

Strongly Correlated Electrons · Physics 2022-08-16 Jixun K. Ding , Wen O. Wang , Brian Moritz , Yoni Schattner , Edwin W. Huang , Thomas P. Devereaux

We investigate the three-dimensional structure of the pulsar magnetosphere through time-dependent numerical simulations of a magnetic dipole that is set in rotation. We developed our own Eulerian finite difference time domain numerical…

Astrophysics · Physics 2009-11-13 Constantinos Kalapotharakos , Ioannis Contopoulos

We present preliminary results of a 3D MHD simulation of the convective envelope of the giant star Pollux for which the rotation period and the magnetic field intensity have been measured from spectroscopic and spectropolarimetric…

Solar and Stellar Astrophysics · Physics 2016-11-25 A. Palacios , A. S. Brun

The stability of ferromagnetism at the surface at finite temperatures is investigated within the strongly correlated Hubbard model on a semi-infinite lattice. Due to the reduced surface coordination number the effective Coulomb correlation…

Strongly Correlated Electrons · Physics 2009-10-31 T. Herrmann , W. Nolting

We present and validate a novel semi-analytical approach to study the effect of dynamical friction on the orbits of massive perturbers in rotating stellar discs. We find that dynamical friction efficiently circularises the orbit of…

Astrophysics of Galaxies · Physics 2020-04-22 Matteo Bonetti , Elisa Bortolas , Alessandro Lupi , Massimo Dotti , Sandra I. Raimundo

We present the results of large scale, three-dimensional magneto-hydrodynamics simulations of disc-winds for different initial magnetic field configurations. The jets are followed from the source to 90 AU scale, which covers several pixels…

Solar and Stellar Astrophysics · Physics 2015-06-23 Jan Staff , Nico Koning , Rachid Ouyed , Adam Thompson , Ralph Pudritz

We study the ascending motion of a disk rolling on an incline when its center of mass lies outside the disk axis. The problem is suitable as laboratory project for a first course in mechanics at the undergraduate level and goes beyond…

Physics Education · Physics 2014-08-06 Lisandro A. Raviola , Oscar Zárate , Eduardo E. Rodríguez

We report an experimental approach to excite, stabilize, and continuously track Bloch sphere orbits of dipolar-coupled nuclear spins in a solid. We demonstrate these results on a model system of hyperpolarized 13C nuclear spins in diamond.…

We present the first three-dimensional magnetohydrodynamic (MHD) simulations of a circumbinary disk surrounding an equal mass binary. The binary maintains a fixed circular orbit of separation $a$. As in previous hydrodynamical simulations,…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Ji-Ming Shi , Julian H. Krolik , Stephen H. Lubow , John F. Hawley

We report simulations of a frustrated odd-numbered macrospin ring system, with full point dipolar interactions, driven by a rotating uniform applied magnetic field of constant magnitude. The system is designed with equally-spaced…

Materials Science · Physics 2014-09-23 J. P. Morgan , R. P. Cowburn

The formation of protoplanetary discs during the collapse of molecular dense cores is significantly influenced by angular momentum transport, notably by the magnetic torque. In turn, the evolution of the magnetic field is determined by…

Astrophysics of Galaxies · Physics 2017-02-01 Patrick Hennebelle , Benoit Commercon , Gilles Chabrier , Pierre Marchand

We investigate the dynamics of magnetic fields in spiral galaxies by performing 3D MHD simulations of galactic discs subject to a spiral potential. Recent hydrodynamic simulations have demonstrated the formation of inter-arm spurs as well…

Astrophysics · Physics 2009-11-13 C. L. Dobbs , D. J. Price