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We study here the phenomena of decayless kink oscillations in a system of active region (AR) coronal loops. Using high resolution observations from two different instruments, namely the Extreme Ultraviolet Imager (EUI) on board Solar…

Cardiac and respiratory rhythms are known to exhibit a modest degree of phase synchronization, which is affected by age, diseases, and other factors. We study the fine temporal structure of this synchrony in healthy young, healthy elderly,…

Tissues and Organs · Quantitative Biology 2021-04-26 Sungwoo Ahn , Jessica Solfest1 , Leonid L Rubchinsky

We explore the effect of an inhomogeneous mass density field on frequencies and wave profiles of torsional Alfven oscillations in solar coronal loops. Dispersion relations for torsional oscillations are derived analytically in limits of…

Astrophysics · Physics 2019-08-19 T. V. Zaqarashvili , K Murawski

We have analyzed H-alpha intensity images obtained at a 1 minute cadence with the Global Oscillation Network Group (GONG) system to investigate the properties of oscillations in the 0-8 mHz frequency band at the location and time of strong…

Solar and Stellar Astrophysics · Physics 2018-03-08 Teresa Monsue , Frank Hill , Keivan G. Stassun

We investigated the effect of time delays on phase configurations in a set of two-dimensional coupled phase oscillators. Each oscillator is allowed to interact with its neighbors located within a finite radius, which serves as a control…

Pattern Formation and Solitons · Physics 2009-11-07 Seong-Ok Jeong , Tae-Wook Ko , Hie-Tae Moon

Recent high-resolution observations of sunspot oscillations using simultaneously operated ground- and space-based telescopes reveal the intrinsic connection between different layers of the solar atmosphere. However, it is not clear whether…

Solar and Stellar Astrophysics · Physics 2015-10-13 S. Krishna Prasad , D. B. Jess , Elena Khomenko

We introduce the concept of phase-synchronous undersampling in nonlinear spectroscopy. The respective theory is presented and validated experimentally in a phase-modulated quantum beat experiment by sampling high phase modulation…

Chemical Physics · Physics 2018-03-14 Lukas Bruder , Marcel Binz , Frank Stienkemeier

Understanding the effects of the lower solar atmosphere on the spectrum of standing kink oscillations of coronal loops, in both the decaying and decayless regime, is essential for developing more advanced tools for coronal seismology. We…

Solar and Stellar Astrophysics · Physics 2025-01-07 Konstantinos Karampelas , Daye Lim , Tom Van Doorsselaere , Yuhang Gao

The phenomenon of slow switching in populations of globally coupled oscillators is discussed. This characteristic collective dynamics, which was first discovered in a particular class of the phase oscillator model, is a result of the…

Disordered Systems and Neural Networks · Physics 2009-10-31 Hiroshi Kori , Yoshiki Kuramoto

Coupled oscillator networks provide mathematical models for interacting periodic processes. If the coupling is weak, phase reduction -- the reduction of the dynamics onto an invariant torus -- captures the emergence of collective dynamical…

Dynamical Systems · Mathematics 2024-08-06 Christian Bick , Tobias Böhle , Christian Kuehn

Propagating perturbations have been observed in extended coronal loop structures for a number of years, but the interpretation in terms of slow (propagating) magneto-acoustic waves and/or as quasi-periodic upflows remains unresolved. We…

Solar and Stellar Astrophysics · Physics 2015-10-06 Ineke De Moortel , Patrick Antolin , Tom Van Doorsselaere

We present numerical studies of the nonlinear, resistive magnetohydrodynamic (MHD) evolution of coronal loops. For these simulations we assume that the loops carry no net current, as might be expected if the loop had evolved due to vortex…

Astrophysics · Physics 2009-10-31 T. D. Arber , A. W. Longbottom , R. A. M. Van der Linden

It is found that both microflare-sized impulsive heating at one leg of the loop and a suddenly imposed velocity perturbation can propel the prominence to oscillate along the magnetic dip. An extensive parameter survey results in a scaling…

Solar and Stellar Astrophysics · Physics 2015-06-15 Q. M. Zhang , P. F. Chen , C. Xia , R. Keppens , H. S. Ji

This work investigates the decayless kink oscillations of solar coronal loops and examines possible changes in their behaviour in active regions (ARs) before powerful solar flares (M- and X-class) and in the absence of powerful flares. To…

Solar and Stellar Astrophysics · Physics 2025-11-10 A. B. Nechaeva , I. V. Zimovets , I. N. Sharykin , S. A. Anfinogentov

A new method for automated coronal loop tracking, in both spatial and temporal domains, is presented. Applying this technique to TRACE data, obtained using the 171 Angstrom filter on 1998 July 14, we detect a coronal loop undergoing a 270s…

Astrophysics · Physics 2009-11-13 D. B. Jess , M. Mathioudakis , R. Erdelyi , G. Verth , R. T. J. McAteer , F. P. Keenan

In the recent work of Nakariakov et al. (2004), it has been shown that the time dependences of density and velocity in a flaring loop contain pronounced quasi-harmonic oscillations associated with the 2nd harmonic of a standing slow…

Astrophysics · Physics 2008-06-10 D. Tsiklauri , V. M. Nakariakov , T. D. Arber , M. J. Aschwanden

Transverse oscillations that do not show significant damping in solar coronal loops are found to be ubiquitous. Recently, the discovery of high-frequency transverse oscillations in small-scale loops has been accelerated by the Extreme…

Solar and Stellar Astrophysics · Physics 2023-08-08 Daye Lim , Tom Van Doorsselaere , David Berghmans , Richard J. Morton , Vaibhav Pant , Sudip Mandal

In the past few years observations by high-resolution space imaging telescopes and spectrometers have confirmed that a great variety of MHD waves are supported in the solar corona of a low-beta plasma and fine structure. MHD waves are an…

Astrophysics · Physics 2007-05-23 Tongjiang Wang

Using data obtained by the EUV Imaging Spectrometer (EIS) onboard Hinode, we have per- formed a survey of obvious and persistent (without significant damping) Doppler shift oscillations in the corona. We have found mainly two types of…

Solar and Stellar Astrophysics · Physics 2012-10-31 Hui Tian , Scott W. McIntosh , Tongjiang Wang , Leon Ofman , Bart De Pontieu , Davina E. Innes , Hardi Peter

Biological systems can rely on collective formation of a metachronal wave in an ensemble of oscillators for locomotion and for fluid transport. We consider one-dimensional chains of phase oscillators with nearest neighbor interactions,…

Biological Physics · Physics 2023-03-15 A. C. Quillen