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Related papers: Enhanced Joule Heating in Umbral Dots

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Current burning issues in stellar physics, for both hot and cool stars, concern their magnetism. In hot stars, stable magnetic fields of fossil origin impact their stellar structure and circumstellar environment, with a likely major role in…

Solar and Stellar Astrophysics · Physics 2019-03-18 C. Neiner , J. Morin , J. -C. Bouret , L. Fossati

The domain wall depinning from a notch in a Permalloy nanostrip on top of a ${\rm SiO_2/Si}$ substrate is studied theoretically under application of static magnetic fields and the injection of short current pulses. The influence of Joule…

Mesoscale and Nanoscale Physics · Physics 2016-07-15 Simone Moretti , Victor Raposo , Eduardo Martinez

Understanding the relationship between the magnetic field and coronal heating is one of the central problems of solar physics. However, studies of the magnetic properties of impulsively heated loops have been rare. We present results from a…

Solar and Stellar Astrophysics · Physics 2019-06-12 Ignacio Ugarte-Urra , Nicholas A. Crump , Harry P. Warren , Thomas Wiegelmann

Recent progress in theoretical modeling of a sunspot is reviewed. The observed properties of umbral dots are well reproduced by realistic simulations of magnetoconvection in a vertical, monolithic magnetic field. To understand the penumbra,…

Solar and Stellar Astrophysics · Physics 2015-05-13 John H. Thomas

We investigate the thermal properties of circular semiconductor quantum dots in high magnetic fields using finite temperature Hartree-Fock techniques. We demonstrate that for a given magnetic field strength quantum dots undergo various…

Strongly Correlated Electrons · Physics 2009-11-07 D. J. Dean , J. C. Wells , M. R. Strayer

Nowadays, magnetic hyperthermia constitutes a complementary approach to cancer treatment. The use of magnetic particles as heating mediators, proposed in the 1950s, provides a novel strategy for improving tumor treatment and, consequently,…

Imposing a magnetic field on a turbulent flow of electrically conducting fluid incurs the Joule effect. A current paradigm is that the corresponding dissipation increases with the intensity of the magnetic field, and as a result turbulent…

Fluid Dynamics · Physics 2017-07-05 Alban Pothérat , Rico Klein

We study the mutual influence of thermal and magnetic evolution in a neutron star's crust in axial symmetry. Taking into account realistic microphysical inputs, we find the heat released by Joule effect consistent with the circulation of…

Astrophysics · Physics 2010-11-02 J. A. Pons , J. A. Miralles , U. Geppert

The sunspot penumbra is a transition zone between the strong vertical magnetic field area (sunspot umbra) and the quiet Sun. The penumbra has a fine filamentary structure that is characterized by magnetic field lines inclined toward the…

Solar and Stellar Astrophysics · Physics 2010-12-02 I. N. Kitiashvili , A. G. Kosovichev , N. N. Mansour , A. A. Wray

We continue the study of the effects of a strong magnetic field on the temperature distribution in the crust of a magnetized neutron star (NS) and its impact on the observable surface temperature. Extending the approach initiated in Geppert…

Astrophysics · Physics 2009-11-11 U. Geppert , M. Kueker , Dany Page

Umbral dots (UDs) are small-scale convective intrusions in the umbral core of sunspots and pores. Different methods have been used in the past to determine the physical properties of UDs. One of the methods typically used is multi-level…

Solar and Stellar Astrophysics · Physics 2026-05-27 Rohan Eugene Louis , Amit Chaturvedi

In this work we study numerically the influence of a homogeneous electrical field on the fluid and heat transfer phenomena at macroscale and mesoscale during unidirectional solidification of a binary metal alloy. The numerical results…

Materials Science · Physics 2007-07-04 P. A. Nikrityuk , K. Eckert , R. Grundmann

We consider the electrical current through a magnetic point contact in the limit of a strong inelastic scattering of electrons. In this limit local Joule heating of the contact region plays a decisive role in determining the transport…

Materials Science · Physics 2009-11-11 A. Kadigrobov , S. I. Kulinich , R. I. Shekhter , M. Jonson , V. Korenivski

We study the effect of an external magnetic field on coherent backscattering of light from a cool rubidium vapor. We observe that the backscattering enhancement factor can be {\it increased} with $B$. This surprising behavior shows that the…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Olivier Sigwarth , Guillaume Labeyrie , Thibaut Jonckheere , Dominique Delande , Robin Kaiser , Christian Miniatura

We theoretically investigate the enhancement of thermoelectric cooling performance in thermoelectric devices made of materials with inhomogeneous thermal conductivity, beyond the usual practice of enhancing thermoelectric figure of merit…

Mesoscale and Nanoscale Physics · Physics 2016-02-11 Tingyu Lu , Jun Zhou , Nianbei Li , Ronggui Yang , Baowen Li

We studied a circular-ribbon flare, SOL2014-12-17T04:51, with emphasis on its thermal evolution as determined by the Differential Emission Measure (DEM) inversion analysis of the extreme ultraviolet (EUV) images of the Atmospheric Imaging…

Solar and Stellar Astrophysics · Physics 2020-08-13 Jeongwoo Lee , Judith T. Karpen , Chang Liu , Haimin Wang

One candidate-model for heating the solar corona is magnetic reconnection that embodies Ohmic dissipation of current sheets. When numerous small-scaled magnetic reconnection occur, then it is possible to heat the corona. Due to the…

Solar and Stellar Astrophysics · Physics 2018-09-19 Charalambos Kanella , Boris V. Gudiksen

The solution for the MHD flow, due to a linearly stretching sheet, has a simple form for the velocity field, with a companion simple form for the induced magnetic field. The associated thermal problem, including viscous dissipation and…

Fluid Dynamics · Physics 2019-11-19 Tarek M. A. El-Mistikawy

Chromospheric observations of sunspot umbrae offer an exceptional view of magneto-acoustic shock phenomena and the impact they have on the surrounding magnetically-dominated plasma. We employ simultaneous slit-based spectro-polarimetry and…

Solar and Stellar Astrophysics · Physics 2018-06-13 S. J. Houston , D. B. Jess , A. Asensio Ramos , S. D. T. Grant , C. Beck , A. A. Norton , S. Krishna Prasad

(Abridged) We here investigate, by means of fully 3-D Smoothed Particle Magnetohydrodynamic numerical simulations, the effects of magnetic fields on overdense, radiatively cooling, pulsed jets, using different initial magnetic field…

Astrophysics · Physics 2009-11-06 Adriano H. Cerqueira , Elisabete M. de Gouveia Dal Pino