English
Related papers

Related papers: Enhanced Joule Heating in Umbral Dots

200 papers

The phenomenon of unipolar induction consists in generating electric field by uniformly rotating permanent magnets made of either conducting or dielectric substance. The origin of the field around conducting magnets is explained and…

General Physics · Physics 2010-11-09 P. Hraskó

Recent experiments demonstrated unexpected, even intriguing properties of certain glassy materials in magnetic field at low temperatures. We have studied the magnetic field dependence of the static dielectric susceptibility and the heat…

Disordered Systems and Neural Networks · Physics 2007-10-12 Alireza Akbari , D. Bodea , A. Langari

The electrical and Hall conductivities in a uniform magnetic field are evaluated for an interacting pion gas using the kinetic theory approach within the ambit of relaxation time approximation (RTA). The in-medium cross sections vis-a-vis…

High Energy Physics - Phenomenology · Physics 2020-10-21 Pallavi Kalikotay , Snigdha Ghosh , Nilanjan Chaudhuri , Pradip Roy , Sourav Sarkar

We investigate the relaxation of braided magnetic loops in order to find out how the type of braiding via footpoint motions affects resultant heating of the loop. Two magnetic loops, braided in different ways, are used as initial conditions…

Solar and Stellar Astrophysics · Physics 2015-06-03 A. L. Wilmot-Smith , D. I. Pontin , A. R. Yeates , G. Hornig

Various observations of magnetic fields in the Intra-Cluster Medium (ICM), most of the time restricted to cluster cores, point towards field strength of the order of a few microG (synchrotron radiation from radio relics and radio halos,…

Astrophysics · Physics 2009-11-13 Y. Dubois , R. Teyssier

We describe the characteristics and evolution of the magnetic field and chromospheric emission in an active region core observed by the Solar Optical Telescope on Hinode. Consistent with previous studies, we find that the moss is unipolar,…

Solar and Stellar Astrophysics · Physics 2015-05-19 David H. Brooks , Harry P. Warren , Amy R. Winebarger

One of the fundamental properties of astrophysical magnetic fields is their ability to change topology through reconnection and in doing so, to release magnetic energy, sometimes violently. In this work, we review recent results on the role…

High Energy Astrophysical Phenomena · Physics 2015-05-18 E. M. de Gouveia Dal Pino , G. Kowal , L. H. S. Kadowaki , P. Piovezan , A. Lazarian

To deepen the analysis of the photometric properties of the umbra of a sunspot, we study proper motions of small features such as umbral dots (UDs) inside a single sunspot observed by the Solar Optical Telescope of Hinode close to the disk…

Solar and Stellar Astrophysics · Physics 2018-07-17 Hadis Goodarzi , Serge Koutchmy , Ali Adjabshirizadeh

The magnetic phases of a triangular-lattice antiferromagnet, CuCrO$_2$, were investigated in magnetic fields along to the $c$ axis, $H$ // [001], up to 120 T. Faraday rotation and magneto-absorption spectroscopy were used to unveil the rich…

Strongly Correlated Electrons · Physics 2017-11-22 Atsuhiko Miyata , Oliver Portugall , Daisuke Nakamura , Kenya Ohgushi , Shojiro Takeyama

We study thermalization on rotating probe branes in AdS_5 x S^5 background in the presence of constant external electric and magnetic fields. In the AdS/CFT framework this corresponds to thermalization in the flavour sector in field theory.…

High Energy Physics - Theory · Physics 2015-06-16 M. Ali-Akbari , H. Ebrahim , Z. Rezaei

We study the effect of an applied magnetic field on sub-10nm wide MoGe and Nb superconducting wires. We find that magnetic fields can enhance the critical supercurrent at low temperatures, and does so more strongly for narrower wires. We…

Superconductivity · Physics 2009-11-11 A. Rogachev , T. -C. Wei , D. Pekker , A. T. Bollinger , P. M. Goldbart , A. Bezryadin

A second emission enhancement in warm coronal extreme-ultraviolet (EUV) lines (about 2-7 MK) during some solar flares is known as the EUV late phase. Imaging observations confirm that the late phase emission originates from a set of longer…

Solar and Stellar Astrophysics · Physics 2019-06-19 Zhenjun Zhou , Xin Cheng , Lijuan Liu , Yu Dai , Yuming Wang , Jun Cui

At finite temperature a breakdown of the hard thermal loop expansion arises whenever external momenta are light-like or tend to very soft scales. A resummation of ladder graphs is important in these cases where the effects of infrared or…

High Energy Physics - Phenomenology · Physics 2009-10-31 E. Petitgirard

We study the effect of a perpendicular uniform magnetic field on the dissipative conductivity of a rectangular lattice with anisotropic hopping, $t_x\neq t_y $. We show that the magnetic field may enhance dramatically the directional…

Condensed Matter · Physics 2009-10-31 Armelle Barelli , Jean Bellissard , Francisco Claro

We describe a scenario for the sunspot magnetic field topology that may account for recent observations of upflows and downflows in penumbrae. According to our conjecture, short narrow magnetic loops fill the penumbral volume. Flows along…

Astrophysics · Physics 2008-11-27 J. Sanchez Almeida

Umbral flashes (UFs) are most common phenomenon of wave processes in sunspots. Studying the relationship between wave time dynamics and the origin of UFs requires further investigation of their fine spatial and height structure. We…

Solar and Stellar Astrophysics · Physics 2018-10-24 R. Sych , M. Wang

Magnetars, neutron stars thought to be with ultra-strong magnetic fields of $10^{14 - 15}$ G, are observed to be much hotter than ordinary pulsars with $\sim 10^{12}$ G, and additional heating sources are required. One possibility is…

High Energy Astrophysical Phenomena · Physics 2023-03-29 Sachiko Tsuruta , Madeline J. Kelly , Ken'ichi Nomoto , Kanji Mori , Marcus Teter , Andrew C. Liebmann

We use mixed correlators in thermal CFT as clean probes of the strong gravity effects in their holographic duals. The dual interpretation of mixing is an inelastic conversion of one field to another field, induced by gravity: tidal…

High Energy Physics - Theory · Physics 2021-09-01 Julius Engelsöy , Bo Sundborg

Penumbrae are known to be area of mainly horizontal magnetic field surrounding umbrae of relatively large and mature sunspots. In this paper, we observationally studied the formation of penumbrae in NOAA10978, where several penumbral…

Solar and Stellar Astrophysics · Physics 2015-06-22 Reizaburo Kitai , Hiroko Watanabe , Ken'ichi Otsuji

Two sequences of solar images obtained by the Transition Region and Coronal Explorer in three UV passbands are studied using wavelet and Fourier analysis and compared to the photospheric magnetic flux measured by the Michelson Doppler…