243 citations · 1.4k across the 49 of their papers we have counts for
44 papers · 1 filter
The Study of Quasi-Periodic Pulsations in Solar and Stellar Flares with SKA
Valery M. Nakariakov, Atul Mohan, Vishal Upendran +5
An intensively studied phenomenon which is not described by the standard flare model are quasi-periodic pulsations (QPP) of the flaring emission. As analysis of the QPP phenomenon…
Power-law Indices of EUV Intensity Power Spectrum in Flaring Coronal Active Regions
Sihui Zhong, Dmitrii Y. Kolotkov, Valery M. Nakariakov
Solar intensity power spectra are usually characterised by coloured noise, with the spectral energy following a segmented power-law function of frequency, , ove…
A 50-min coronal kink oscillation and its possible photospheric counterpart
Sihui Zhong, Valery M. Nakariakov, Dmitrii Y. Kolotkov
A coronal loop of 290~Mm length, observed at 171~Å with SDO/AIA on February 6th 2024 near AR 13571, is found to oscillate with two significantly different oscillation periods, $48.…
Detection of kink oscillations in solar coronal loops by a CNN-LSTM neural network
Sergey A. Belov, Yu Zhong, Dmitrii Y. Kolotkov +1
A hybrid machine learning model which combines a shallow convolutional neural network and a long short-term memory network (CNN--LSTM), has been developed to automate the detection…
The effect of thermal misbalance on magnetohydrodynamic modes in coronal magnetic cylinders
S. M. Hejazi, T. Van Doorsselaere, M. Sadeghi +2
This study investigates the dispersion of magnetohydrodynamic waves influenced by thermal misbalance in a cylindrical configuration with a finite axial magnetic field within solar…
Undersampling effects on observed periods of coronal oscillations
Daye Lim, Tom Van Doorsselaere, Valery M. Nakariakov +3
Context. Recent observations of decayless transverse oscillations have shown two branches in the relationship between periods and loop lengths. One is a linear relationship, interp…
Effects of the photospheric cut-off on the p-mode frequency stability
Dmitrii Y. Kolotkov, Anne-Marie Broomhall, Amir Hasanzadeh
Sub-photospheric acoustic resonators allow for the formation of standing p-mode oscillations by reflecting acoustic waves with frequencies below the acoustic cut-off frequency. We…
Detecting quasi-periodic pulsations in solar and stellar flares with a neural network
Sergey A. Belov, Dmitrii Y. Kolotkov, Valery M. Nakariakov +1
Quasi-periodic pulsations (QPP) are often detected in solar and stellar flare lightcurves. These events may contain valuable information about the underlying fundamental plasma dyn…
Transition from decaying to decayless kink oscillations of solar coronal loops
Valery M. Nakariakov, Yu Zhong, Dmitrii Y. Kolotkov
The transition of an impulsively excited kink oscillation of a solar coronal loop to an oscillation with a stationary amplitude, i.e., the damping pattern, is determined using the…
Diagnostics of the solar coronal plasmas by magnetohydrodynamic waves: Magnetohydrodynamic seismology
Valery M. Nakariakov, Sihui Zhong, Dmitrii Y. Kolotkov +3
Macroscopic wave and oscillatory phenomena ubiquitously detected in the plasma of the corona of the Sun are interpreted in terms of magnetohydrodynamic theory. Fast and slow magnet…
The centroid speed as a characteristic of the group speed of solar coronal fast magnetoacoustic wave trains
Dmitrii Y. Kolotkov, Valery M. Nakariakov, Maximilien Cloesen
The highly-filamented nature of the coronal plasma significantly influences dynamic processes in the corona such as magnetohydrodynamic waves and oscillations. Fast magnetoacoustic…
Polarisation of decayless kink oscillations of solar coronal loops
Sihui Zhong, Valery M. Nakariakov, Dmitrii Y. Kolotkov +4
Decayless kink oscillations of plasma loops in the solar corona may contain an answer to the enigmatic problem of solar and stellar coronal heating. The polarisation of the oscilla…
Bayesian evidence for two slow-wave damping models in hot coronal loops
I. Arregui, D. Y. Kolotkov, V. M. Nakariakov
We compute the evidence in favour of two models, one based on field-aligned thermal conduction alone and another that includes thermal misbalance as well, in explaining the damping…
Stability of slow magnetoacoustic and entropy waves in the solar coronal plasma with thermal misbalance
Dmitrii Y. Kolotkov, Valery M. Nakariakov, Joseph B. Fihosy
The back-reaction of the perturbed thermal equilibrium in the solar corona on compressive perturbations, also known as the effect of wave-induced thermal misbalance, is known to re…
Coronal seismology by slow waves in non-adiabatic conditions
Dmitrii Y. Kolotkov
Slow magnetoacoustic waves represent an important tool for probing the solar coronal plasma. We quantitatively assess the applicability of the weak thermal conduction theory to cor…
Do Periods of Decayless Kink Oscillations of Solar Coronal Loops Depend on Noise?
Valery M. Nakariakov, Dmitrii Y. Kolotkov, Sihui Zhong
Decayless kink oscillations of solar coronal loops are studied in terms of a low-dimensional model based on a randomly driven Rayleigh oscillator with coefficients experiencing ran…
Two-Spacecraft Detection of Short-period Decayless Kink Oscillations of Solar Coronal Loops
Sihui Zhong, Valery M. Nakariakov, Dmitrii Y. Kolotkov +2
Decayless kink oscillations of an ensemble of loops are captured simultaneously by the High Resolution Imager (HRI) of the Extreme Ultraviolet Imager (EUI) and the Atmospheric Imag…
Cycle dependency of a quasi-biennial variability in the solar interior
T. Mehta, K. Jain, S. C. Tripathy +3
We investigated the solar cycle dependency on the presence and periodicity of the Quasi-Biennial Oscillation (QBO). Using helioseismic techniques, we used solar oscillation frequen…
Doubling of minute-long Quasi-Periodic Pulsations from super-flares on a low mass star
J. Gerry Doyle, Puji Irawati, Dmitrii Y. Kolotkov +5
Using the ULTRASPEC instrument mounted on the 2.4-m Thai National Telescope, we observed two large flares, each with a total energy close to 10^34 erg with sub-second cadence. A co…
A new look at the frequency-dependent damping of slow-mode waves in the solar corona
Dmitrii Y. Kolotkov, Valery M. Nakariakov
Being directly observed in the Doppler shift and imaging data and indirectly as quasi-periodic pulsations in solar and stellar flares, slow magnetoacoustic waves offer an important…
New Time-Resolved, Multi-Band Flares In The GJ 65 System With gPhoton
Scott W. Fleming, Chase Million, Rachel A. Osten +2
Characterizing the distribution of flare properties and occurrence rates is important for understanding habitability of M dwarf exoplanets. The GALEX space telescope observed the G…
Novel data analysis techniques in coronal seismology
Sergey A. Anfinogentov, Patrick Antolin, Andrew R. Inglis +7
We review novel data analysis techniques developed or adapted for the field of coronal seismology. We focus on methods from the last ten years that were developed for extreme ultra…
Multi-wavelength quasi-periodic pulsations in a stellar superflare
Dmitrii Y. Kolotkov, Valery M. Nakariakov, Robin Holt +1
We present the first multi-wavelength simultaneous detection of QPP in a superflare (more than a thousand times stronger than known solar flares) on a cool star, in soft X-rays (SX…
The solar corona as an active medium for magnetoacoustic waves
D. Y. Kolotkov, D. I. Zavershinskii, V. M. Nakariakov
The presence and interplay of continuous cooling and heating processes maintaining the corona of the Sun at the observed one million K temperature were recently understood to have…