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Related papers: Averaging of magnetic fields and applications

200 papers

The current state of research of the Galactic magnetic field is reviewed critically. The average (equipartition) strength of the total field derived from radio synchrotron data is 6 +/- 2 muG locally and about 10 +/- 3 muG at 3 kpc Galactic…

Astrophysics · Physics 2021-04-28 Rainer Beck

The Dirac equation for an electron in two spatial dimensions in the Coulomb and homogeneous magnetic fields is discussed. For weak magnetic fields, the approximate energy values are obtained by semiclassical method. In the case with strong…

Quantum Physics · Physics 2009-11-06 Choon-Lin Ho , V. R. Khalilov

The weak-field approximation is one of the simplest models that allows us to relate the observed polarization induced by the Zeeman effect with the magnetic field vector present on the plasma of interest. It is usually applied for…

Solar and Stellar Astrophysics · Physics 2015-05-27 A. Asensio Ramos

Weak magnetic fields must have existed in the early Universe, as they were sourced by the cross product of electron density and temperature gradients through the Biermann-battery mechanism. In this paper we calculate the magnetic fields…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-15 Nanoom Lee , Yacine Ali-Haimoud

{Although there is considerable evidence supporting an ubiquitous magnetic field in solar/stellar photospheres, its impact in the determination of abundances has never been quantified. In this work we investigate whether the magnetic field…

Astrophysics · Physics 2009-11-13 J. M. Borrero

We study the infimum of the Ginzburg-Landau functional in the case of a vanishing external magnetic field in a two dimensional simply connected domain. We obtain an energy asymptotics which is valid when the Ginzburg-Landau parameter is…

Analysis of PDEs · Mathematics 2015-03-17 Bernard Helffer , Ayman Kachmar

For the magnetic Laplacian on a bounded planar domain, imposing Neumann boundary conditions produces eigenvalues below the lowest Landau level. If the domain has two boundary components and one imposes a Neumann condition on one component…

Spectral Theory · Mathematics 2024-06-11 Soeren Fournais , Ayman Kachmar

One of the most intriguing features of Earth's axial magnetic dipole field, well-known from the geological record, is its occasional and unpredictable reversal of polarity. Understanding the phenomenon is rendered very difficult by the…

Geophysics · Physics 2019-01-02 Christian R. Scullard , Bruce A. Buffett

Key diagnostics of non-thermal plasmas, such as the position of the synchrotron self-absorption turnover or the Faraday rotation optical depth, depend crucially on the unobserved low-energy electron spectrum. We investigate the effect of…

Astrophysics · Physics 2007-05-23 Christian Hettlage , Karl Mannheim

We study the Ginzburg-Landau energy of a superconductor with a variable magnetic field and a pinning term in a bounded smooth two dimensional domain $\Omega$. Supposing that the Ginzburg-Landau parameter and the intensity of the magnetic…

Analysis of PDEs · Mathematics 2015-03-24 Kamel Attar

We study the magnetic Laplacian in a two-dimensional exterior domain with Neumann boundary condition and uniform magnetic field. For the exterior of the disk we establish accurate asymptotics of the low-lying eigenvalues in the weak…

Spectral Theory · Mathematics 2024-05-29 Ayman Kachmar , Vladimir Lotoreichik , Mikael Sundqvist

We continue the analysis started in [Noris,Terracini,Indiana Univ Math J,2010] and [Bonnaillie-No\"el,Noris,Nys,Terracini,Analysis & PDE,2014], concerning the behavior of the eigenvalues of a magnetic Schr\"odinger operator of Aharonov-Bohm…

Analysis of PDEs · Mathematics 2014-11-20 Benedetta Noris , Manon Nys , Susanna Terracini

In the Dirac operator framework we characterize and estimate the ground state energy of relativistic hydrogenic atoms in a constant magnetic field and describe the asymptotic regime corresponding to a large field strength using relativistic…

Analysis of PDEs · Mathematics 2009-11-11 Jean Dolbeault , Maria J. Esteban , Michael Loss

Gravitational lensing allows to quantify the angular distribution of the convergence field around clusters of galaxies to constrain their connectivity to the cosmic web. We describe in this paper the corresponding theory in Lagrangian space…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Sandrine Codis , Raphael Gavazzi , Christophe Pichon , Celine Gouin

We develop sharp upper bounds for energy levels of the magnetic Laplacian on starlike plane domains, under either Dirichlet or Neumann boundary conditions and assuming a constant magnetic field in the transverse direction. Our main result…

Mathematical Physics · Physics 2014-01-07 R. S. Laugesen , B. A. Siudeja

We are concerned with the dependence of the lowest eigenvalue of the magnetic Dirichlet Laplacian on the geometry of rectangles, subject to homogeneous fields. We conjecture that the square is a global minimiser both under the area or…

Spectral Theory · Mathematics 2025-08-25 David Krejcirik

We study $\Gamma$-convergence of graph Dirichlet energies and spectral convergence of graph Laplacians on unions of intersecting manifolds of potentially different dimensions. Our investigation is motivated by problems of machine learning,…

Analysis of PDEs · Mathematics 2025-09-30 Leon Bungert , Dejan Slepčev

We describe a first attempt to derive properties of the regular and turbulent Galactic magnetic field from multi-frequency polarimetric observations of the diffuse Galactic synchrotron background. A single-cell-size model of the thin…

Astrophysics · Physics 2009-11-10 M. Haverkorn , P. Katgert , A. G. de Bruyn

We consider the first eigenvalue of the magnetic Laplacian in a bounded and simply connected planar domain, with uniform magnetic field and Neumann boundary conditions. We investigate the reverse Faber-Krahn inequality conjectured by S.…

Spectral Theory · Mathematics 2024-11-27 Bruno Colbois , Corentin Léna , Luigi Provenzano , Alessandro Savo

We consider the Neumann realization of the magnetic laplacian in $\mathbb{R}^3_+$, in the case in which the magnetic field has a piecewise constant strength and a uniform direction. This operator is expected to be an effective model in…

Analysis of PDEs · Mathematics 2022-07-29 Emanuela L. Giacomelli