English
Related papers

Related papers: Evolution of safety factor profiles in sawteeth

200 papers

Recent spectropolarimetric surveys of main-sequence intermediate-mass stars have exhibited a dichotomy in the distribution of the observed magnetic field between the kG dipoles of Ap/Bp stars and the sub-Gauss magnetism of Vega and Sirius.…

Solar and Stellar Astrophysics · Physics 2015-08-12 Mathieu Gaurat , Laurène Jouve , François Lignières , Thomas Gastine

An accidental U(1) Peccei-Quinn (PQ) symmetry automatically arises in a class of SO(10) unified theories upon gauging the SU(3)$_{f}$ flavour group. The PQ symmetry is protected by the $\mathbb{Z}_4 \times \mathbb{Z}_3$ center of…

High Energy Physics - Phenomenology · Physics 2020-12-02 Luca Di Luzio

We characterize real and complex functions which, when applied entrywise to square matrices, yield a positive definite matrix if and only if the original matrix is positive definite. We refer to these transformations as sign preservers.…

Classical Analysis and ODEs · Mathematics 2026-05-08 Dominique Guillot , Himanshu Gupta , Prateek Kumar Vishwakarma , Chi Hoi Yip

We study the evolution of kink instability in a force-free, non-rotating plasma column of high magnetization. The main dissipation mechanism is identified as reconnection of magnetic field-lines with various intersection angles, driven by…

High Energy Astrophysical Phenomena · Physics 2019-10-16 Omer Bromberg , Chandra B. Singh , Jordy Davelaar , Alexander A. Philippov

A novel effect involving the formation of a stable kink-like torsion deformation in a magnetoactive elastomer (MAE) beam subjected to a uniform magnetic field is theoretically predicted and experimentally confirmed. The phenomenon was…

We study truncation compatible families F = (F_m)_{m>=1} over Q[z] through an inverse limit formalism, and we evaluate them at the punctured cyclotomic cosine points alpha_{k,n} = cos(2 pi k/n) with the specialization z equals n-1. For…

Combinatorics · Mathematics 2026-02-10 Juan D. Velez , Carlos Cadavid

We consider the numerical taxonomy problem of fitting a positive distance function ${D:{S\choose 2}\rightarrow \mathbb R_{>0}}$ by a tree metric. We want a tree $T$ with positive edge weights and including $S$ among the vertices so that…

Data Structures and Algorithms · Computer Science 2022-03-14 Vincent Cohen-Addad , Debarati Das , Evangelos Kipouridis , Nikos Parotsidis , Mikkel Thorup

The magnetohydrodynamic linear stability with the localized bulk flow oriented parallel to the neutral sheet is investigated, by including the Hall effect and the guide magnetic field. We observe three different unstable modes: a "streaming…

Space Physics · Physics 2015-05-19 Masahiro Hoshino

Fe$^{3+}$ $S = 5/2$ ions form saw-tooth like chains along the $a$ axis of the oxo-selenite Fe$_2$O(SeO$_3$)$_2$ and an onset of long-range magnetic order is observed for temperatures below $T_C = 105$ K. This order leads to distinct…

Kinetic simulations have demonstrated that three-dimensional reconnection in collisionless regimes proceeds through the formation and interaction of magnetic flux ropes, which are generated due to the growth of tearing instabilities at…

Plasma Physics · Physics 2016-02-17 Cihan Akcay , William Daughton , Vyacheslav S. Lukin , Yi-Hsin Liu

We analyze situations where a saddle-node bifurcation occurs on a fractal basin boundary. Specifically, we are interested in what happens when a system parameter is slowly swept in time through the bifurcation. Such situations are known to…

Chaotic Dynamics · Physics 2009-11-10 Romulus Breban , Helena E. Nusse , Edward Ott

The linear stability of MHD Taylor-Couette flow of infinite vertical extension is considered for liquid sodium with its small magnetic Prandtl number Pm of order of 10^-5 and an uniform axial magnetic field. The sign of the constant a in…

Astrophysics · Physics 2016-08-16 G. Rüdiger , M. Schultz , D. Shalybkov

We study the consequences of twisting the Poincare invariance in a quantum field theory. First, we construct a Fock space compatible with the twisting and the corresponding creation and annihilation operators. Then, we show that a covariant…

High Energy Physics - Theory · Physics 2010-10-27 E. Joung , J. Mourad

Fast magnetic reconnection is defined by the topology of the magnetic field lines changing on a timescale that is approximately an order of magnitude longer than the topology-conserving ideal-evolution timescale. Fast reconnection is an…

Plasma Physics · Physics 2022-05-18 Allen H Boozer

Foundation models are routinely fine-tuned for use in particular domains, yet safety assessments are typically conducted only on base models, implicitly assuming that safety properties persist through downstream adaptation. We test this…

Computers and Society · Computer Science 2026-04-29 Emaan Bilal Khan , Amy Winecoff , Miranda Bogen , Dylan Hadfield-Menell

It is demonstrated how the correction factor alpha used in Hall magnetometry of localized magnetic field profiles depends on the sample geometry and on the electron mean free path, in the quasi-ballistic and ballistic regimes, for weak and…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 M. Cerchez , T. Heinzel

This study seeks to characterise the breakdown of the steady 2D solution in the flow around a 180-degree sharp bend to infinitesimal 3D disturbances using a linear stability analysis. The stability analysis predicts that 3D transition is…

Fluid Dynamics · Physics 2017-08-30 Azan M. Sapardi , Wisam K. Hussam Alban Pothérat , Gregory J. Sheard

Spherically symmetric, asymptotically flat solutions of Shape Dynamics were previously studied assuming standard falloff conditions for the metric and the momenta. These ensure that the spacetime is asymptotically Minkowski, and that the…

General Relativity and Quantum Cosmology · Physics 2016-09-21 Flavio Mercati

The problem of the stability of magnetic fields in stars has a long history and has been investigated in detail in perturbation theory. Here we consider the nonlinear evolution of a non-rotating neutron star with a purely poloidal magnetic…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Riccardo Ciolfi , Samuel K. Lander , Gian Mario Manca , Luciano Rezzolla

We address the study of gauge invariance in the Standard Model Extension which encompasses all Lorentz-violating terms originated by spontaneous symmetry breaking at the Planck scale. In particular, we fully evaluate Ward identities…

High Energy Physics - Theory · Physics 2016-01-29 A. R. Vieira , A. L. Cherchiglia , Marcos Sampaio