On the Physical Nature of the so-Called Prominence Tornadoes

Space Science Reviews, Год журнала: 2023, Номер 219(4)

Опубликована: Май 24, 2023

Abstract The term ‘tornado’ has been used in recent years to describe several solar phenomena, from large-scale eruptive prominences small-scale photospheric vortices. It also applied the generally stable quiescent prominences, sparking a renewed interest what historically was called ‘prominence tornadoes’. This paper carries out an in-depth review of physical nature tornadoes’, where their name subconsciously makes us think violent rotational dynamics. However, after careful consideration and analysis published observational data theoretical models, we conclude that tornadoes’ do not differ any substantial way other prominences. There is simply no unequivocal evidence sustained coherent movements would justify distinct category sharing with well-known atmospheric phenomenon. visual impression column-like silhouettes, perceived helical motions, or suggestive Doppler-shift patterns all have simpler, more likely explanation. They are consequence projection effects combined presence oscillations and/or counter-streaming flows. ‘Prominence thus just manifestations complex when observed specific projections. These coincidental viewing angles, together fine-structure dynamics simple yet profoundly distorting effects, may sometimes play havoc our intuitive understanding shapes leading incorrect analogy tornadoes.

Язык: Английский

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Lagrangian coherent structures in space plasmas

Reviews of Modern Plasma Physics, Год журнала: 2023, Номер 7(1)

Опубликована: Ноя. 5, 2023

Язык: Английский

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Swirls in the solar corona

Astronomy and Astrophysics, Год журнала: 2023, Номер 675, С. A94 - A94

Опубликована: Май 17, 2023

Vortex flows have been found in the photosphere, chromosphere and low corona observations simulations. It has suggested that vortices play an important role for channeling energy plasma into corona, but impact of vortex on not directly studied a realistic setup. We investigate coronal heating using high resolution simulations loops. The are artificially driven, arise self-consistently from magnetoconvection. perform 3D resistive MHD with MURaM code. Studying isolated loop Cartesian geometry allows us to resolve structure interior. conduct statistical analysis determine properties as function height corona. find injected is generated by internal coherent motions within strong magnetic elements. A significant part resulting Poynting flux channeled through tubes forming connection between photosphere Vortices can form contiguous structures reach up heights, itself get deformed eventually lose their identity increasing height. show increased upward directed rate both effect becomes less pronounced While transport structuring importance higher atmosphere clear since swirls distinguishable environment. reaching complex relationship emission.

Язык: Английский

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A spectroscopic investigation of thermal instability for cylindrical equilibria with background flow

Astronomy and Astrophysics, Год журнала: 2024, Номер 686, С. A180 - A180

Опубликована: Март 25, 2024

Context. Flows are omnipresent and govern the dynamics of plasma. Solar tornadoes a class apparently rotating prominences that might be formed by thermal instability. In spectroscopic studies on instability, background flow is commonly neglected. Aims. We here determine effect instability in cylindrical magnetic field configurations. How various parameters affect distribution eigenmodes magnetohydrodynamic (MHD) spectrum also explored. investigate whether discrete modes exist. Methods. an analytical study, we extended upon literature including generic coordinate system. The non-adiabatic MHD equations linearised, Fourier-analysed, examined to understand how changes continua. An approximate expression for derived using Wentzel-Kramers-Brillouin (WKB) analysis. results then verified benchmark equilibrium eigenvalue code Legolas . eigenfunctions visualised 2D 3D. Results. continuum Doppler-shifted due flow, just like slow Alfvén Discrete altered because governing contain flow-related terms. predict appearance based derived. All expressions match numerical results. density perturbations not uniform or singular condensation, shape dependence assumed waveform coordinates wavenumbers. A 3D visualisation total velocity shows helical heavily influenced radial perturbation. Conclusions. analytic with them coronal equilibrium. However, valid can applied other astrophysical environments.

Язык: Английский

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Mathematical foundation of Liutex theory

Journal of Hydrodynamics, Год журнала: 2022, Номер 34(6), С. 981 - 993

Опубликована: Дек. 1, 2022

Язык: Английский

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Alfvén Waves in the Solar Atmosphere

Geophysical monograph, Год журнала: 2024, Номер unknown, С. 3 - 38

Опубликована: Апрель 12, 2024

Alfvén waves are propagating disturbances of magnetic tension and one the fundamental in plasma at large scales. The study solar corona has a long continuing tradition, started way before were found to be ever-present atmosphere. Their is important for mainly two reasons. First, might play key role long-standing chromospheric coronal heating problems, as well solar-wind acceleration problem, both transmitting energy photospheric convection higher up atmosphere more directly means cascading dissipating this through various mechanisms. Second, observed properties can used infer seismology. In review, an overview basic theoretical understanding magnetohydrodynamic (MHD) presented, attempt clarify that greater class MHD encountered Furthermore, observational findings on previous decade reviewed, followed by short summary these results still open questions.

Язык: Английский

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Poynting Flux of MHD Modes in Magnetic Solar Vortex Tubes

The Astrophysical Journal, Год журнала: 2024, Номер 975(2), С. 176 - 176

Опубликована: Ноя. 1, 2024

Abstract Magnetic flux tubes in the presence of background rotational flows, known as solar vortex tubes, are abundant throughout atmosphere and may act conduits for MHD waves to transport magnetic energy upper atmosphere. We aim investigate Poynting associated with these within tubes. model a tube straight azimuthal velocity component. The wave solutions equilibrium configuration obtained using Shooting Eigensolver SolAr Magnetohydrostatic Equilibria code we derive an expression vertical component flux, S z , modes. In addition, present 2D visualizations spatial structure different modes under flow strengths. show that increases when compared no flow. When strength is greater than 100 times perturbation, non-axisymmetric (∣ m ∣ > 0) by over 1000% absence Furthermore, fundamental property vortices, namely they cannot solely produce upward untwisted tube, meaning any observed must arise from perturbations, such waves.

Язык: Английский

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Comparison of Liutex and Other Vortex Identification Methods Based on Vortex Models

Springer proceedings in physics, Год журнала: 2024, Номер unknown, С. 20 - 33

Опубликована: Янв. 1, 2024

Язык: Английский

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Advanced Γ Method for Small-scale Vortex Detection in the Solar Atmosphere

The Astrophysical Journal Supplement Series, Год журнала: 2023, Номер 267(2), С. 35 - 35

Опубликована: Авг. 1, 2023

Abstract Ubiquitous vortical structures are considered to act as a natural source of various solar plasma phenomena, for example, wide range magnetohydrodynamic waves and jet excitations. This work aims develop an advanced vortex detection algorithm based on the Γ method using separable convolution kernel technique. is applied detect analyze photospheric vortices in 3D realistic magnetoconvection numerical observational data. We present (AGM), our results indicate that AGM performs with better accuracy comparison original method. The allows us identify small- large-scale no interposition without requiring changing threshold. In this way, nondetection issue mostly prevented. It was found failed large longer-lived vortices, which were detected by AGM. size tends vary over time, most shrinking toward their end. vorticity at center also not constant, presenting sharp decay ceases exist. Due its capability identifying minimum nondetection, properties—such lifetime, geometry, dynamics—are captured than era new high-resolution observation, can be used precise technique performing statistical analysis atmospheric vortices.

Язык: Английский

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Influence of ambipolar and Hall effects on vorticity in three-dimensional simulations of magneto-convection

Philosophical Transactions of the Royal Society A Mathematical Physical and Engineering Sciences, Год журнала: 2020, Номер 379(2190)

Опубликована: Дек. 21, 2020

This paper presents the results of analysis three-dimensional simulations solar magneto-convection that include joint action ambipolar diffusion and Hall effect. Three simulation runs are compared: one including both effect; only without any these two effects. The magnetic field is amplified from initial to saturation level by turbulent local dynamo. In each cases, we study 2 h simulated time after dynamo reaches regime. We analyse power spectra vorticity, fluctuations different components Poynting flux responsible for transport vertical or horizontal perturbations. Our preliminary show produces a strong reduction vorticity in upper chromospheric layers it dissipates vortical perturbations converting them into thermal energy. effect acts opposite way, strongly enhancing vorticity. When included, becomes, on average, more long-lived tube-like structures produced. trace single structure its evolution pattern intensification, their possible relation article part Theo Murphy meeting issue ‘High-resolution wave dynamics lower atmosphere’.

Язык: Английский

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