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Related papers: Sharp dynamic points in Earth-Sun physics

200 papers

We theoretically study coherent subharmonic (multi-photon) transitions of a harmonically driven spin. We consider two cases: magnetic resonance (MR) with a misaligned, i.e., non-transversal driving field, and electrically driven spin…

Mesoscale and Nanoscale Physics · Physics 2015-08-19 Judit Romhányi , Guido Burkard , András Pályi

One of the most fascinating and puzzling aspects of non-Hermitian systems is their spectral degeneracies, i.e., exceptional points (EPs), at which both eigenvalues and eigenvectors coalesce to form a defective state space. While coupled…

Mesoscale and Nanoscale Physics · Physics 2023-03-08 Kuangyin Deng , Xin Li , Benedetta Flebus

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

Magneto-Rossby waves in the solar tachocline are currently considered to be one of the main determinants of solar activity. In particular, they can give rise to the quasi-biennial oscillation (QBO). The latter was recently shown to be…

Solar and Stellar Astrophysics · Physics 2026-02-13 F. Stefani , G. M. Horstmann , G. Mamatsashvili , T. Weier

Drawing connections between heliospheric spacecraft and solar wind sources is a vital step in understanding the evolution of the solar corona into the solar wind and contextualizing \textit{in situ} timeseries. Furthermore, making advanced…

We consider a setting in which an evolving surface is implicitly characterized as the zero level of a level set function. Such an implicit surface does not encode any information about the path of a single point on the evolving surface. In…

Numerical Analysis · Mathematics 2026-02-02 Tilman Aleman , Arnold Reusken

We investigate the low-energy effective theory of a Fermi surface coupled to an Ising-nematic quantum critical point in (2+1) spacetime dimensions with translation symmetry. We formulate the system using the large $N$ Yukawa-SYK model,…

Strongly Correlated Electrons · Physics 2026-03-12 Haoyu Guo

In this study we used the sea surface temperature (SST), El-Nino southern oscillation (ENSO) and Pacific decadal oscillation (PDO) time-series for the time period 1900-2012 in order to investigate plausible manifestation of sharp increases…

Atmospheric and Oceanic Physics · Physics 2013-03-08 Belolipetsky P. V. , Bartsev S. I. , Degermendzhi A. G. , Huang-Hsiung Hsu , Varotsos C. A.

Umbral dots (UDs) were observed in a stable sunspot in NOAA 10944 by the Hinode Solar Optical Telescope on 2007 March 1. The observation program consisted of blue continuum images and spectropolarimetric profiles of Fe I 630 nm line. An…

Solar and Stellar Astrophysics · Physics 2015-05-13 Hiroko Watanabe , Reizaburo Kitai , Kiyoshi Ichimoto

The location of the terrestrial magnetopause (MP) and it's subsolar stand-off distance depends not only on the solar wind dynamic pressure and the interplanetary magnetic field (IMF), both of which play a crucial role in determining it's…

Space Physics · Physics 2017-09-06 Madhusudan Ingale , P. Janardhan , K. Fujiki , Susanta Kumar Bisoi , Diptiranjan Rout

We investigated the solar cycle dependency on the presence and periodicity of the Quasi-Biennial Oscillation (QBO). Using helioseismic techniques, we used solar oscillation frequencies from the Global Oscillations Network Group (GONG),…

Solar and Stellar Astrophysics · Physics 2022-08-02 T. Mehta , K. Jain , S. C. Tripathy , R. Kiefer , D. Kolotkov , A. -M. Broomhall

In 1844 Schwabe discovered that the number of sunspots increased and decreased over a period of about 11 years, that variation became known as the sunspot cycle. Almost eighty years later, Hale described the nature of the Sun's magnetic…

Using even-order frequency splitting coefficients of global p-modes it is possible to infer the magnetic field in the solar interior as a function of radial distance and latitude. Results obtained using GONG and MDI data are discussed.…

Astrophysics · Physics 2007-05-23 H. M. Antia

Magnetic reconnection is a key mechanism involved in solar eruptions and is also a prime possibility to heat the low corona to millions of degrees. Here, we present ultra-high-resolution extreme ultraviolet observations of persistent…

Recent work suggests that (stochastic) gradient descent self-organizes near an instability boundary, shaping both optimization and the solutions found. Momentum and mini-batch gradients are widely used in practical deep learning…

Machine Learning · Computer Science 2026-04-16 Arseniy Andreyev , Advikar Ananthkumar , Marc Walden , Tomaso Poggio , Pierfrancesco Beneventano

Solar quasi-biennial oscillations with period range 0.6 to 4 years, are prominent in records of solar activity. Here we show that the 1.6 year quasi-biennial oscillation in solar activity has the exceptional feature of phase inversion…

Solar and Stellar Astrophysics · Physics 2021-10-27 Ian R. Edmonds

The primary focus of this paper is on the particle acceleration mechanism in solar coronal three-dimensional reconnection null-point regions. Starting from a potential field extrapolation of a Solar and Heliospheric Observatory (SOHO)…

Solar and Stellar Astrophysics · Physics 2013-07-09 G. Baumann , T. Haugbølle , Å. Nordlund

We present a study of wave processes occurring in solar active region NOAA 11131 on 2010 December 10, captured by the Solar Dynamics Observatory in the 1600A, 304A, and 171A channels. For spectral analysis we employed pixelised wavelet…

Solar and Stellar Astrophysics · Physics 2021-01-20 Robert Sych , David B. Jess , Jiangtao Su

The solar atmosphere is extremely dynamic, and many important phenomena develop on small scales that are unresolved in observations with the Helioseismic and Magnetic Imager (HMI) instrument on the Solar Dynamics Observatory (SDO). For…

Solar and Stellar Astrophysics · Physics 2015-08-06 Irina N. Kitiashvili , Sebastien Couvidat , Andreas Lagg

We consider the Earth-Moon planar circular restricted three body problem and present a proof of the existence orbits, which approach arbitrarily close to one of the primary masses, and at the same time after each approach they move away…

Dynamical Systems · Mathematics 2024-01-24 Maciej J. Capiński , Aleksander Pasiut