Valeriia Liakh

• Liakh, V. & Keppens, R. (2025). Numerical study of solar eruption, extreme-ultraviolet wave propagation, and wave-induced prominence dynamics. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 696. doi: 10.1051/0004-6361/202453300. Fulltekst i vitenarkiv Vis sammendrag

  Context. Extreme ultraviolet (EUV) waves, frequently produced by eruptions, propagate through the non-uniform magnetic field of the solar corona and interact with distant prominences, inducing their global oscillations. However, the generation, propagation, and interaction of these waves with distant prominences remain poorly understood. Aims. We aim to study the influence of an eruptive flux rope (EFR) on a distant prominence by means of extreme-resolution numerical simulations. We cover a domain of a horizontal extent of 1100 Mm, while capturing details down to 130 km using automated grid refinement. Methods. We performed a 2.5D numerical experiment using the open-source MPI-AMRVAC 3.1 code, modeling an eruption as a 2.5D catastrophe scenario augmented with a distant dipole magnetic field to form a flux rope prominence. Results. Our findings reveal that the EFR becomes unstable and generates a quasi-circular front. The primary front produces a slow secondary front when crossing the equipartition lines where the Alfvén speed is close to the sound speed. The resulting fast (primary) and slow (secondary) EUV waves show different behaviors: the fast EUV wave slightly decelerates as it propagates through the corona, while the slow EUV wave forms a stationary front. The fast EUV wave interacts with the remote prominence, driving both transverse and longitudinal oscillations. Additionally, magnetic reconnection at a null point below the prominence-hosting flux rope is triggered by the fast EUV wave, affecting the flux rope magnetic field and the prominence oscillations. Conclusions. Our study unifies important results of the dynamics of eruptive events and their interactions with distant prominences, including details of (oscillatory) reconnection and chaotic plasmoid dynamics. We demonstrate for the first time the full consequences of remote eruptions on prominence dynamics and clarify the damping mechanisms of prominence oscillations.

• Liakh, Valeriia & Jenkins, Jack (2025). Numerical Modeling of Prominences and Coronal Rain with the MPI-AMRVAC Code. Solar Physics. ISSN 0038-0938. 300(10). doi: 10.1007/s11207-025-02552-7. Fulltekst i vitenarkiv Vis sammendrag

  This review surveys recent advances in the numerical modeling of solar prominences and coronal rain achieved with the fully open-source adaptive-grid, parallelized Adaptive Mesh Refinement Versatile Advection Code (MPI-AMRVAC). We examine how these models have contributed to our understanding of the formation and evolution of cool plasma structures in the solar corona. We first discuss prominence models that focus on prominence formation and their dynamic behaviour. We then turn to coronal rain, highlighting its connection to thermal instability and its role in the exchange of mass and energy between the corona and chromosphere. Particular attention is given to the growing efforts to connect simulations with observations through synthetic emission and spectral diagnostics.

• Luna, Manuel; Joshi, Reetika; Schmieder, Birgitte; Moreno-Insertis, Fernando; Liakh, Valeriia & Terradas, Jaume (2024). Study of the excitation of large-amplitude oscillations in a prominence by nearby flares. Astronomy and Astrophysics (A & A). ISSN 0004-6361. 691. doi: 10.1051/0004-6361/202450869. Fulltekst i vitenarkiv Vis sammendrag

  Context. Large-amplitude oscillations are a common occurrence in solar prominences. These oscillations are triggered by energetic phenomena such as jets and flares. On March 14–15, 2015, a filament partially erupted in two stages, leading to oscillations in different parts of it. Aims. In this study, we aim to explore the longitudinal oscillations resulting from the eruption, with special focus on unravelling the underlying mechanisms responsible for their initiation. We pay special attention to the huge oscillation on March 15. Methods. The oscillations and jets were analysed using the time-distance technique. For the study of flares and their interaction with the filament, we analysed the different AIA channels in detail and used the differential-emission-measure (DEM) technique. Results. In the initial phase of the event, a jet induces the fragmentation of the filament, which causes it to split into two segments. One of the segments remains in the same position, while the other is detached and moves to a different location. This causes oscillations in both segments: (a) the change of position apparently causes the detached segment to oscillate longitudinally with a period of 69 ± 3 minutes; (b) the jet flows reach the remaining filament also producing longitudinal oscillations with a period of 62 ± 2 minutes. In the second phase, on March 15, another jet seemingly activates the detached filament eruption. After the eruption, there is an associated flare. A large longitudinal oscillation is produced in the remnant segment with a period of 72 ± 2 minutes and a velocity amplitude of 73 ± 16. During the triggering of the oscillation, bright field lines connect the flare with the filament. These only appear in the AIA 131 Å and 94 Å channels, indicating that they contain very hot plasma. The DEM analysis also confirms this result. Both indicate that a plasma of around 10 MK pushes the prominence from its south-eastern side, displacing it along the field lines and initiating the oscillation. From this evidence, the flare and not the preceding jet initiates the oscillation. The hot plasma from the flare escapes and flows into the filament channel structure. Conclusions. In this paper, we shed light on how flares can initiate the huge oscillations in filaments. We propose an explanation in which part of the post-flare loops reconnect with the filament channel’s magnetic-field lines that host the prominence.

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• Liakh, Valeriia (2026). Prominence Modeling in the Era of High-Resolution Solar Observations. Fulltekst i vitenarkiv Vis sammendrag

  Prominences are complex but fascinating phenomena observed in the outer region of the solar atmosphere, the solar corona. Interest in these structures is driven by space weather research in the context of the initiation of coronal mass ejections. Prominences demonstrate a wide variety of morphologies and dynamics, and despite decades of observational, theoretical, and modeling studies, many aspects of their evolution remain not entirely understood. In this talk, we will discuss examples of the different types of evolution observed in solar prominences, from formation to eruption or, alternatively, gradual disappearance, and how we use numerical modeling to explain the physical processes behind them. We will also highlight the perspectives for synergistic studies in the era of high-resolution solar observations and sophisticated simulations performed with modern numerical codes.

• Liakh, Valeriia; Druett, Malcolm & Dubart, Maxime (2026). 2.5D flare simulations with MPI-AMRVAC. Fulltekst i vitenarkiv
• Liakh, Valeriia (2026). Toward Realistic Modeling of Solar Prominences Across Their Life Cycle. Fulltekst i vitenarkiv Vis sammendrag

  Despite decades of both observational and modeling efforts, a self-consistent picture of the formation and evolution of solar prominences remains unclear. In this talk, we review progress in prominence modeling, beginning with current ideas on their formation and the physical processes responsible for mass supply. We then discuss their subsequent dynamical evolution, including counter-streaming flows, mass drainage, and oscillatory phenomena. Additionally, the modeling of the prominence dynamics will be discussed in the context of the prominence stability. Recent numerical studies highlight the need for increasingly realistic simulations to capture the prominence complexity. Therefore, in the final part of the talk, we outline the major open questions and promising directions for future research needed to strengthen the link between simulations and observations.

• Liakh, Valeriia (2026). Numerical Modeling of Prominence Dynamics induced by Coronal Waves. Fulltekst i vitenarkiv Vis sammendrag

  Energetic events, such as solar flares and eruptions, are frequently accompanied by coronal waves that propagate far from their source region and interact with various structures, including coronal holes, prominences, and coronal loops. Interpreting such interactions with prominences directly from observations remains challenging and requires realistic magnetohydrodynamic (MHD) modeling to understand the underlying physical mechanisms and types of induced oscillation. In this talk, we present recent advances in MHD simulations of the interaction between large-scale coronal waves and solar prominences. Particular emphasis will be placed on the propagation of the coronal waves in the non-uniformly magnetized solar corona, the formation of the secondary fronts, the development of thermal instability within the prominence-hosting flux rope, and the excitation of prominence oscillations.

• Liakh, Valeriia (2025). Numerical study of solar eruption, extreme-ultraviolet wave propagation, and wave-induced prominence dynamics. Fulltekst i vitenarkiv
• Liakh, Valeriia (2025). Coronal Wave–Prominence Interaction and Induced Prominence Dynamics. Fulltekst i vitenarkiv Vis sammendrag

  In this talk, we present results from 2.5D MHD simulations of a solar eruption, the propagation of coronal waves through a non-uniformly magnetized solar corona, and their interaction with remote flux rope prominences, leading to induced prominence dynamics. The initial atmosphere is a non-adiabatic, gravitationally stratified corona permeated by a magnetic field composed of two main components: (1) a 2.5D catastrophe field responsible for triggering the eruption and coronal wave, and (2) a dipolar field used for the subsequent formation of flux rope prominences. Our simulations reveal the formation of a secondary front when the wave produced by the eruption encounters the equipartition layer. The main front steepens into a shock as the wave propagates farther from the eruption site. When reaching the prominence region, the wave generates reflected and transmitted fronts. The wave impact excites complex prominence oscillations, both along the magnetic field and in the vertical direction. Furthermore, the downward push from the wave front triggers magnetic reconnection beneath the prominence flux rope. To improve the comparability of our results with real observations, we generated synthetic images in the 131 Å, 193 Å, and 304 Å SDO/AIA channels

• Liakh, Valeriia (2025). Modeling Solar Prominences: A Space Weather Perspective. Fulltekst i vitenarkiv Vis sammendrag

  Solar prominences are large clouds of cool, dense plasma that hover in the corona, the outer part of the solar atmosphere. They can remain stable for days or even weeks, but sometimes they suddenly erupt, launching massive clouds of plasma into space. Such eruptions are one of the main drivers of space weather, which can disturb satellites, power grids, and communication systems on Earth. Understanding the formation, dynamics, and eruptions of prominences is therefore essential both for fundamental solar physics and for predicting their impact on the near-Earth environment. In this talk, Valeriia will present recent advances in numerical modeling of prominences using state-of-the-art magnetohydrodynamic (MHD) simulations. She will show how such models help us investigate the physical mechanisms behind their formation, oscillations, and eruptions. By synthesizing observables from the simulations, we can also make direct comparisons with space-based and ground-based observations, providing the basis for the interpretation of the observations.

• Liakh, Valeriia (2025). How Do Eruptive Events Affect Distant Prominences? Insights from Numerical Simulations. Fulltekst i vitenarkiv Vis sammendrag

  Extreme ultraviolet (EUV) waves generated by solar eruptions propagate through the magnetized corona, interacting with distant prominences and inducing their oscillations. However, the mechanisms governing these interactions remain incompletely understood. We present results from high-resolution numerical simulations performed with MPI-AMRVAC, modeling an eruptive flux rope (EFR) and its effects on a remote prominence. The eruption generates a fast EUV wave that propagates through the corona, inducing transverse and longitudinal prominence oscillations and triggering reconnection at a null point below the prominence-hosting flux rope. We analyze the impact of different background magnetic field configurations on wave propagation, reconnection dynamics, and prominence stability. Synthetic EUV images provide observational context for our results, offering an interpretation of the observations.

• Liakh, Valeriia (2025). Modeling of Eruption–Prominence Interaction in the Solar Corona. Fulltekst i vitenarkiv

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