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Modeling the Excitation, Propagation and Damping of Quasi-Periodic Fast Magnetosonic Waves in Realistic Coronal Active Region Magnetic Field Structures
Leon Ofman, Tongjiang Wang, Xudon Sun +1
Quasi-periodic fast propagating magnetosonic waves (QFPs) were discovered in the solar corona in EUV since the launch of SDO spacecraft more than a decade ago. The QFP waves are as…
Exploring Standing and Reflected Slow-mode Waves in Flaring Coronal Loops: A Parametric Study Using 2.5D MHD Modeling
Tongjiang Wang, Leon Ofman, Stephen J. Bradshaw
Recent observations of reflected propagating and standing slow-mode waves in hot flaring coronal loops have spurred our investigation into their underlying excitation and damping m…
Observations and Modeling of Unstable Proton and Alpha Particle Velocity Distributions in Sub-Alfvenic Solar Wind at PSP Perihelia
Leon Ofman, Scott A Boardsen, Lan K Jian +7
Past observations show that solar wind (SW) acceleration occurs inside the sub-Alfvenic region, reaching the local Alfven speed at typical distances ~ 10 - 20 Rs (solar radii). Rec…
Reconnection generated plasma flows in the quasi-separatrix layer in localised solar corona
Sripan Mondal, A. K. Srivastava, Sudheer K. Mishra +8
Multiwavelength observations of the propagating disturbances (PDs), discovered by Atmospheric Imaging Assembly (AIA) onboard Solar Dynamics Observatory (SDO), are analyzed to deter…
Nonlinear Fast Magnetosonic Waves in Solar Prominence Pillars
Leon Ofman, Therese A. Kucera, C. Richard DeVore
We investigate the properties of nonlinear fast magnetosonic (NFM) waves in a solar prominence, motivated by recent high-resolution and high-cadence Hinode/SOT observations of smal…
Modeling ion beams, kinetic instabilities, and waves observed by the Parker Solar Probe near perihelia
Leon Ofman, Scott A Boardsen, Lan K Jian +2
Recent in-situ observations from the Parker Solar Probe (PSP) mission in the inner heliosphere near perihelia show evidence of ion beams, temperature anisotropies, and kinetic wave…
Excitation and Damping of Slow Magnetosonic Waves in Flaring Hot Coronal Loops: Effects of Compressive Viscosity
Leon Ofman, Tongjiang Wang
Slow magnetosonic waves associated with flares were observed in coronal loops by SOHO/SUMER, SDO/AIA in various EUV bandpasses, and other instruments. The excitation and damping of…
Slow-Mode Magnetoacoustic Waves in Coronal Loops
Tongjiang Wang, Leon Ofman, Ding Yuan +3
Rapidly decaying long-period oscillations often occur in hot coronal loops of active regions associated with small (or micro-) flares. This kind of wave activity was first discover…
Coronal heating by MHD waves
Tom Van Doorsselaere, Abhishek K. Srivastava, Patrick Antolin +9
The heating of the solar chromosphere and corona to the observed high temperatures, imply the presence of ongoing heating that balances the strong radiative and thermal conduction…
MHD Waves in open coronal structures
D. Banerjee, S. Krishna Prasad, V. Pant +8
Modern observatories have revealed the ubiquitous presence of magnetohydrodynamic waves in the solar corona. The propagating waves (in contrast to the standing waves) are usually o…
Fast Magnetosonic Waves and Flows in a Solar Prominence Foot: Observations and Modeling
Leon Ofman, Therese A. Kucera
We study recent observations of propagating fluctuations in a prominence foot with Hinode Solar Optical Telescope (SOT) high-resolution observations in Ca~II and H alpha emission w…
Determination of transport coefficients by coronal seismology of flare-induced slow-mode waves: Numerical parametric study of 1D loop model
Tongjiang Wang, Leon Ofman
Recent studies of a flaring loop oscillation event on 2013 December 28 observed by the Atmospheric Imaging Assembly (AIA) of the Solar Dynamics Observatory (SDO) have revealed the…
A Truly Global Extreme Ultraviolet Wave from the SOL2017-09-10 X8.2+ Solar Flare-Coronal Mass Ejection
Wei Liu, Meng Jin, Cooper Downs +3
We report SDO/AIA observations of an extraordinary global extreme ultraviolet (EUV) wave triggered by the X8.2+ flare-CME eruption on 2017 September 10. This was one of the best EU…
Effect of transport coefficients on excitation of flare-induced standing slow-mode waves in coronal loops
Tongjiang Wang, Leon Ofman, Xudong Sun +2
Standing slow-mode waves have been recently observed in flaring loops by the Atmospheric Imaging Assembly (AIA) of the Solar Dynamics Observatory (SDO). By means of the coronal sei…
Quasi-periodic Counter-propagating Fast Magnetosonic Wave Trains from Neighboring Flares: SDO/AIA Observations and 3D MHD Modeling
Leon Ofman, Wei Liu
Since their discovery by SDO/AIA in EUV, rapid (phase speeds of 1000 km/s), quasi-periodic, fast-mode propagating wave trains (QFPs) have been observed accompanying many solar flar…
Energy release in the solar atmosphere from a stream of infalling prominence debris
Andrew R. Inglis, Holly R. Gilbert, Leon Ofman
Recent high-resolution and high-cadence EUV imaging has revealed a new phenomenon, impacting prominence debris, where prominence material from failed or partial eruptions can impac…
Slow-Mode Oscillations of Hot Loops Excited at Flaring Footpoints
Tongjiang Wang, Wei Liu, Leon Ofman +1
The analysis of a hot loop oscillation event using SOHO/SUMER, GOES/SXI, and RHESSI observations is presented. Damped Doppler shift oscillations were detected in the Fe XIX line by…
Excitation of flare-induced waves in coronal loops and the effects of radiative cooling
Elena Provornikova, Leon Ofman, Tongjiang Wang
EUV imaging observations from several space missions (SOHO/EIT, TRACE, and SDO/AIA) have revealed a presence of propagating intensity disturbances in solar coronal loops. These dis…
Kelvin--Helmholtz instability in a twisting solar polar coronal hole jet observed by \emph{SDO}/AIA
I. Zhelyazkov, T. V. Zaqarashvili, L. Ofman +1
We investigate the conditions under which the fluting (), , and magnetohydrodynamic (MHD) modes in a uniformly twisted flux tube moving along its axis become…
Halpha Doppler shifts in a tornado in the solar corona
B. Schmieder, P. Mein, N. Mein +3
High resolution movies in 193 A from the Atmospheric Imaging Assembly (AIA) on the Solar Dynamic Observatory SDO show apparent rotation in the leg of a prominence observed during a…
Inference of Magnetic Field in the Coronal Streamer Invoking Kink Wave Motions generated by Multiple EUV Waves
A. K. Srivastava, Talwinder Singh, Leon Ofman +1
Using MHD seismology by observed kink waves, the magnetic field profile of a coronal streamer has been investigated. STEREO-B/EUVI temporal image data on 7 March 2012 shows an evol…
Quasi-periodic Fast-mode Magnetosonic Wave Trains Within Coronal Waveguides Associated with Flares and CMEs
Wei Liu, Leon Ofman, Brittany Broder +2
Quasi-periodic, fast-mode, propagating wave trains (QFPs) are a new observational phenomenon recently discovered in the solar corona by the Solar Dynamics Observatory with extreme…
Evidence of thermal conduction suppression in hot coronal loops: Supplementary results
Tongjiang Wang, Leon Ofman, Xudong Sun +2
Slow magnetoacoustic waves were first detected in hot (6 MK) flare loops by the SOHO/SUMER spectrometer as Doppler shift oscillations in Fe XIX and Fe XXI lines. Recently, such…
Stability of rotating magnetized jets in the solar atmosphere. I. Kelvin-Helmholtz instability
T. V. Zaqarashvili, I. Zhelyazkov, L. Ofman
Observations show various jets in the solar atmosphere with significant rotational motions, which may undergo instabilities leading to heat ambient plasma. We study the Kelvin-Helm…