English
Related papers

Related papers: A Fractal Analysis of Magnetograms within Active R…

200 papers

We present spectropolarimetric analysis of umbral dots and a light bridge fragment that show dark lanes in G-band images. Umbral dots show upflow as well as associated positive Stokes V area asymmetry in their central parts. Larger umbral…

Astrophysics · Physics 2009-11-13 Lokesh Bharti , Chandan Joshi , S. N. A. Jaaffrey , Rajmal Jain

We study numerically the coarsening kinetics of a two-dimensional ferromagnetic system with aleatory bond dilution. We show that interfaces between domains of opposite magnetisation are fractal on every lengthscale, but with different…

Statistical Mechanics · Physics 2019-05-30 Federico Corberi , Leticia F. Cugliandolo , Ferdinando Insalata , Marco Picco

Most of the known methods for estimating the fractal dimension of fractal sets are based on the evaluation of a single geometric characteristic, e.g. the volume of its parallel sets. We propose a method involving the evaluation of several…

Metric Geometry · Mathematics 2015-06-22 Evgeny Spodarev , Peter Straka , Steffen Winter

After a short introduction on how we get information of the magnetic fields from radio observations I discuss the results concerning the magnetic field structure in galaxies: Large-scale regular magnetic field pattern of spiral structure…

Astrophysics · Physics 2007-05-23 M. Krause

It has recently been suggested that conduction-driven magnetohydrodynamic (MHD) instabilities may operate at all radii within an intracluster medium (ICM), and profoundly affect the structure of a cluster's magnetic field. Where MHD…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Tamara Bogdanovic , Christopher Reynolds , Richard Massey

Aims. We aim to infer information about the magnetic field in the low solar corona from coronal rain clumps using high-resolution spectropolarimetric observations in the Ca ii 8542 A line obtained with the Swedish 1-m Solar Telescope.…

Solar and Stellar Astrophysics · Physics 2021-06-09 M. Kriginsky , R. Oliver , P. Antolin , D. Kuridze , N. Freij

We studied Faraday rotation measure (RM) in turbulent media with the rms Mach number of unity, using isothermal, magnetohydrodynamic turbulence simulations. Four cases with different values of initial plasma beta were considered. Our main…

Astrophysics of Galaxies · Physics 2014-11-20 Qingwen Wu , Jongsoo Kim , Dongsu Ryu , Jungyeon Cho , Paul Alexander

We employ high-spatial resolution spectropolarimetric observations from the Solar Optical Telescope on-board the Hinode spacecraft to investigate the fine structure of the penumbral magnetic fields. The Stokes vector of two neutral iron…

Astrophysics · Physics 2009-11-13 J. M. Borrero , B. W. Lites , S. K. Solanki

PET/CT with F-18-Fluorodeoxyglucose (FDG) images of patients suffering from metastatic melanoma have been analysed using fractal and multifractal analysis to assess the impact of monoclonal antibody ipilimumab treatment with respect to…

We study the polar magnetism near an activity maximum when these regions change their polarity, from which it is expected that its magnetism should be less affected by the global field. To fully characterise the magnetic field vector, we…

Solar and Stellar Astrophysics · Physics 2018-08-15 A. Pastor Yabar , M. J. Martínez González , M. Collados

Magnetic fields in galaxy clusters have been measured using a variety of techniques, including: studies of synchrotron relic and halo radio sources within clusters, studies of inverse Compton X-ray emission from clusters, surveys of Faraday…

Astrophysics · Physics 2009-11-07 C. L. Carilli , G. B. Taylor

In this paper, we explore a fractal model of the universe proposed by Calcagni [JHEP{\bf03}(2010)120] for a power-counting renormalizable field theory living in a fractal spacetime. Considering a timelike fractal profile, we derived field…

General Relativity and Quantum Cosmology · Physics 2022-11-01 Mahnaz Asghari , Ahmad Sheykhi

We are developing a new approach to investigate cluster magnetic field strengths and structures. It is based on the comparison of simulated Rotation Measure and radio halo images, obtained from 3-dimensional multi-scale cluster magnetic…

Astrophysics · Physics 2007-05-23 F. Govoni , L. Feretti , M. Murgia , G. B. Taylor , G. Giovannini , D. Dallacasa

Combining high-resolution spectropolarimetric and imaging data is key to understanding the decay process of sunspots as it allows us scrutinizing the velocity and magnetic fields of sunspots and their surroundings. Active region NOAA 12597…

Solar and Stellar Astrophysics · Physics 2018-06-06 M. Verma , C. Denker , H. Balthasar , C. Kuckein , R. Rezaei , M. Sobotka , N. Deng , H. Wang , A. Tritschler , M. Collados , A. Diercke , S. J. González Manrique

A properly calibrated longitudinal magnetograph is an instrument that measures circular polarization and gives an estimation of the magnetic flux density in each observed resolution element. This usually constitutes a lower bound of the…

Solar and Stellar Astrophysics · Physics 2015-05-27 A. Asensio Ramos , M. J. Martinez Gonzalez , R. Manso Sainz

Adopting the thermal free-free emission mechanism, the coronal and chromospheric magnetic fields are derived from the polarization and spectral observations with the Nobeyama Radioheliograph at 1.76 cm. The solar active regions (AR) located…

Solar and Stellar Astrophysics · Physics 2018-02-14 A. Mouner , Abdelrazek M. K. Shaltout , M. M. Beheary , K. A. K. Gadallah , K. A. Edris

Fractal analysis has been shown to be useful in image processing for characterizing shape and gray-scale complexity. The fractal feature is a compact descriptor used to give a numerical measure of the degree of irregularity of the medical…

Computer Vision and Pattern Recognition · Computer Science 2014-09-17 Redouan Korchiyne , Sidi Mohamed Farssi , Abderrahmane Sbihi , Rajaa Touahni , Mustapha Tahiri Alaoui

We establish a Minkowski measurability criterion for a large class of relative fractal drums (or, in short, RFDs), in Euclidean spaces of arbitrary dimension in terms of their complex dimensions, which are defined as the poles of their…

Mathematical Physics · Physics 2023-04-27 Michel L. Lapidus , Goran Radunović , Darko Žubrinić

This work examines the relation between the fractal properties of the photospheric magnetic patterns and those of the coronal magnetic fields in solar active regions.Our results show no correlation between the fractal dimensions of the…

Solar and Stellar Astrophysics · Physics 2015-05-14 M. Dimitropoulou , M. Georgoulis , H. Isliker , L. Vlahos , A. Anastasiadis , D. Strintzi , X. Moussas

As well known, magnetic fields in space are distributed very inhomogeneously. Some-times field distributions have forms of filaments with high magnetic field values. As many ob-servations show, such a filamentation takes place in convective…

Solar and Stellar Astrophysics · Physics 2024-03-03 Evgeny A. Kuznetsov , Evgeny A. Mikhailov