European Solar Physics Online Seminar Archive

Following an initiative by the University of Oslo the MPS will participate in the "European Solar Physics Online Seminar" series (ESPOS). Details can be found here: https://folk.uio.no/tiago/espos/
The aim of this video conference series is to promote ideas more widely with a specialized audience, and give some exposure to cutting-edge research for students and other young researchers that do not regularly travel to conferences. The ESPOS series is planned to take place every second Thursday at 11am.

ESPOS: European Solar Physics Online Seminar (Clara Froment)

ESPOS: ESPOS

ESPOS - European Solar Physics Online Seminar: Theoretical Foundation of 3D Alfven Resonances: Time Dependent Solutions (T. Elsden)

ESPOS
The coupling of fast and Alfven magnetohydrodynamic (MHD) waves is of fundamental interest in astrophysical plasmas. Under certain conditions, Alfven waves can be resonantly excited by fast mode ... [more]

ESP Online Seminar: Magnetic field variations associated with umbral flashes and penumbral waves (J. Joshi)

ESPOS
Oscillations in sunspots have been extensively studied for several decades. Most of the research conducted about sunspot oscillations has focussed around variations in Doppler velocities and ... [more]

ESP Online Seminar: Formation of the penumbra and start of the Evershed Flow (M. Murabito)

ESPOS
Penumbral formation is a significant part of the flux emergence process. Despite the new advanced techniques in observations and simulations, there are still processes that need to be clarified. In ... [more]

ESP Online Seminar: Deep Learning in Solar Physics (A. Asensio Ramos)

ESPOS
Deep learning has emerged as a very powerful set of techniques to extract relevant information from observations, sometimes showing much better results that other set of finely tuned algorithms. In ... [more]

ESP Online Seminar: Spectropolarimetric diagnostics using Sodium D lines (I.Milic)

ESPOS
In this talk we will focus on diagnostic potential of the spectral region around D lines of Sodium. We will first outline our approach to non-lte inversions, and present a method for computation of ... [more]

ESP Online Seminar: Interface Region Imaging Spectrograph views of how the solar (B. de Pontieu) atmosphere is energized

ESPOS
At the interface between the Sun's surface and million-degree outer atmosphere or corona lies the chromosphere. At 10,000K it is much cooler than the corona, but also many orders of magnitude denser ... [more]

ESP Online Seminar: Ca II 8542 Å Brightenings Induced by a Solar Microflare (C. Kuckein)

ESPOS
We study small-scale brightenings in Ca II 8542 Å line-core images to determine their nature and effect on localized heating and mass transfer in active regions. To that end, we analyzed ... [more]
Surges are ubiquitous cool ejections in the solar atmosphere that often appear associated with other interesting phenomena such as UV bursts or coronal jets. Recent observations from the Interface ... [more]

ESP Online Seminar: The Magnetic Nature of the Umbra-Penumbra Boundary in Sunspots (J. Jurčák)

ESPOS
Sunspots are the longest known manifestation of solar activity and their magnetic nature has been known for more than a century. Despite this, the boundary between umbrae and penumbrae, the two ... [more]

ESP Online Seminar: Dissecting bombs and bursts: inversions of reconnection events in SST-IRIS observations (G. Vissers)

ESPOS
Ellerman bombs and UV bursts are transient brightenings that are ubiquitously observed in the lower atmospheres of active and emerging flux regions. While some Ellerman bombs display clear UV burst ... [more]

ESP Online Seminar: What can numerical simulations tell us about the mechanism of solar and stellar activity? (J. Warnecke)

ESPOS
The magnetic field in the Sun undergoes a cyclic modulation with a reversal typically every 11 years due to a dynamo operating under the surface. Also, other solar-like stars exhibit magnetic ... [more]

ESP Online Seminar: Frequency-dependent Damping of Slow Magneto-acoustic Waves in Sunspots (K. Prasad )

ESPOS
Propagating slow magneto-acoustic waves are regularly observed in the solar corona, particularly in sunspot related loop structures. These waves exhibit rapid damping as they propagate along the ... [more]

ESP Online Seminar: Recurrent CME-like Eruptions in Flux Emergence Simulations (P. Syntelis)

ESPOS
Ellerman bombs and UV bursts are transient brightenings that are ubiquitously observed in the lower atmospheres of active and emerging flux regions. While some Ellerman bombs display clear UV burst ... [more]

ESP Online Seminar: Search for predicted periodic flows in loops undergoing thermal non-equilibrium (G. Pelouze)

ESPOS
Long-period intensity pulsations have been recently detected in coronal loops with EUV images of both SoHO/EIT (Auchère et al., 2014) and SDO/AIA (Froment et al., 2015). These pulsations have been ... [more]

ESP Online Seminar: Counter-streaming Flows of a Giant Solar Filament as Observed in the Extreme Ultraviolet (A. Dierke)

ESPOS
A giant solar filament was visible on the solar surface between 8-23 November 2011. The filament stretched over more than half a solar diameter. Multi-wavelength data from the SDO instrument AIA ... [more]
We report multi-wavelength ultraviolet observations taken with the IRIS satellite, concerning the emergence phase in the upper chromosphere and transition region of an emerging flux region (EFR) ... [more]

ESP Online Seminar: Searching for the Origin of Flares in M dwarfs (L. Doyle)

ESPOS
We present an overview of K2 short cadence observations for 32 M dwarfswhich have spectral types between M0-L1. All of the stars in our sampleshowed flares with the most energetic reaching 3x10^34 ... [more]
The strong enhancement of the ultraviolet emission during solar flares is usually taken as an indication of plasma heating in the low solar atmosphere caused by the deposition of the energy released ... [more]

ESP Online Seminar: Multi-height spectropolarimetric study of MHD waves in a big sunspot observed with IBIS (M. Stangalini)

ESPOS
We present preliminary results derived from the analysis of spectropolarimetric measurements of active region AR12546, which represents one of the largest sunspots to have emerged onto the solar ... [more]

ESP Online Seminar: Surface waves and instabilities in the presence of an inclined magnetic field (E. Vickers )

ESPOS
While surface waves propagating at tangential discontinuities have been studied in great detail, few studies have been dedicated to the investigation of the nature of waves at contact discontinuities ... [more]

ESP Online Seminar: Asymmetric Solar Waveguides: Theory and Observations (M. Allcock )

ESPOS
Are solar MHD waveguides symmetric? It is convenient to assume that they are. The solar physics community is familiar with the traditional notion of sausage and kink waves, which propagate along ... [more]

ESP Online Seminar: Ellerman bombs and UV bursts: reconnection at different atmospheric layers? (A. Ortiz)

ESPOS
The emergence of magnetic flux through the photosphere and into the outer solar atmosphere produces, amongst many other phenomena, the appearance of Ellerman bombs (EBs) in the photosphere. EBs are ... [more]
Are some parts of the Interplanetary Magnetic Field’s (IMF) neutral line more flare energetic than others? What are Hale Sector Boundaries (HSBs) and are they connected with flares? Do they have ... [more]
The Wilson depression is the difference in geometric height of the layer of unit continuum optical depth between the sunspot umbra and the quiet Sun. Measuring the Wilson depression is important for ... [more]
Solar observations offer both a rich interdisciplinary laboratory on fundamental astrophysics and precious tools for Space Weather applications. The involved plasma processes determine a complex radio ... [more]
We present high spatial resolution narrow-band images in three different chromospheric spectral lines, including Ca II K with the new CHROMospheric Imaging Spectrometer installed at the Swedish 1-m ... [more]
The ubiquitous presence of small magnetic elements in the Quiet Sun represents a prominent coupling between the photosphere and the upper layers of the Sun’s atmosphere. Small magnetic element ... [more]

ESP Online Seminar: 3D Whole-Prominence Fine Structure models: the current state of the affairs (Stanislav Gunár )

ESPOS
To understand the links between the distribution of the prominence plasma, the configuration of its magnetic field and the observations of prominence/filament fine structures obtained in UV/EUV ... [more]

ESP Online Seminar: The Sun from Coimbra: history, recent results and perspectives (João Fernandes)

ESPOS
The Astronomical Observatory of the Coimbra University has a collection of solar observations on a daily basis, since 1926. We obtain regular observations of the full solar disk using a classical ... [more]

ESP Online Seminar: 2D and 3D Kinematic Analysis of an Ideal-MHD Prominence Eruption (Thomas Rees-Crockford)

ESPOS
We carry out multi-dimensional kinematic analysis of a prominence eruption in order to characterise the role of eruptive ideal-MHD instabilities. Using SDO/AIA and STEREO/EUVI-A we reconstruct the ... [more]
Since the work of Carlin et al. (2012), more studies have investigated, with the help of MHD models of the solar chromosphere, the behavior of scattering linear polarization (LP) in presence of ... [more]

ESP Online Seminar: Swirls and Alfvén pulses in the Solar Atmosphere (JiaJia Liu)

ESPOS

ESP Online Seminar: The largest flares of solar cycle 24 as potential clues for stellar superflares (Paolo Romano)

ESPOS

ESP Online Seminar: Eruptions and flaring activity in emerging quadrupolar regions (Petros Syntelis)

ESPOS

ESP Online Seminar: MHD wave modes in the solar magnetic flux tubes with elliptical cross-section (Anwar Ali Aldhafeeri)

ESPOS

ESP Online Seminar: Spectral diagnostics of cool flare loops observed by SST (Julius Koza)

ESPOS

ESP Online Seminar: Penumbral brightening events (Mariarita Murabito)

ESPOS

ESP Online Seminar: Solar irradiance variability and surface magnetism (Kok Leng Yeo)

ESPOS
The variation in solar irradiance is commonly assumed to be driven by its surface magnetism. Until recently, this assumption could not be verified conclusively as models of solar irradiance ... [more]

ESP Online Seminar: Magnetic Rayleigh–Taylor Unstable Plumes and Hybrid KH-RT Instability into a Loop-like Eruptive Prominence (Sudheer K. Mishra)

ESPOS
The magnetic Rayleigh–Taylor instability is a fundamental MHD instability and recent observations show that this instability develops in the solar prominences. We analyze the observations from Solar ... [more]

ESP Online Seminar: Learning to Invert Solar Flares with RADYN Physics

ESPOS
During a solar flare, it is believed that reconnection takes place in the corona followed by fast energy transport to the chromosphere. The resulting intense heating strongly disturbs the ... [more]

ESP Online Seminar: Learning to Invert Solar Flares with RADYN Physics

ESPOS
During a solar flare, it is believed that reconnection takes place in the corona followed by fast energy transport to the chromosphere. The resulting intense heating strongly disturbs the ... [more]

ESP Online Seminar: Magnetic properties of short-lived penumbral microjets (Azaymi Litzi Siu Tapi)

ESPOS
Studying the polarization properties of penumbral microjets that have the shortest durations requires spectropolarimetric observations with the fastest temporal cadence possible and is currently a ... [more]

ESP Online Seminar: Solar Flare Prediction Using Magnetic Field Diagnostics Above the Photosphere (Marianna Korsos)

ESPOS
We present the application of the weighted horizontal gradient of magnetic field (WGM) flare prediction method to 3D extrapolated magnetic configurations of flaring solar ARs. The main aim is to ... [more]

ESP Online Seminar: Understanding hooks of solar flare ribbons and the evolution of coronal mass ejections (Juraj Lorinčík)

ESPOS
Solar flares and eruptions are one of the most energetic phenomena occuring in the solar system. They are typically described by the cartoon-like 2D Standard model of solar flares. This model is ... [more]

ESP Online Seminar: Study of damping of propagating kink waves in the solar corona (Ajay Tiwari)

ESPOS
Propagating kink waves have been reported recently and have been found to be ubiquitous in the solar corona including in the quiet Sun. It is imperative to understand the mechanisms that enable their ... [more]

ESPOS Online Seminar: The solar atmosphere as observed through the Mg I b2 line at highspatial resolution (Azaymi Litzi Siu-Tapia)

ESPOS
The Mg I b2 line at 5173 Å forms over a large range of heights but itscore, which forms under conditions of non-local thermodynamicequilibrium, is most sensitive to heights near the temperature ... [more]

ESPOS Online Seminar: The solar atmosphere as observed through the Mg I b2 line at highspatial resolution (Azaymi Litzi Siu-Tapia)

ESPOS
The Mg I b2 line at 5173 Å forms over a large range of heights but itscore, which forms under conditions of non-local thermodynamicequilibrium, is most sensitive to heights near the temperature ... [more]

ESPOS Online Seminar: Polarization signatures during the X1.6 flare observed in active region NOAA 12192 (Fabiana Ferrente)

ESPOS
The X1.6 flare observed on 22 October 2014 (SOL2014-10-22T14:28) was among the strongest flares that occurred in the magnetically complex, great active region NOAA 12192. Despite the large amount of ... [more]

ESPOS Online Seminar: Shock-wave radio probing of solar wind sources in coronal magnetic fields (Artem Koval

ESPOS
  • Date: Jul 7, 2021
  • Time: 11:00 AM c.t. - 12:00 PM (Local Time Germany)
  • Speaker: Artem Koval
  • Astronomical Institute of the CAS, Czech Republic
  • Room: Zoom
  • Host: Shahin Jafarzadeh
The Space Weather effects in the near-Earth environment as well as in atmospheres of other terrestrial planets arise by corpuscular radiation from the Sun, known as the solar wind. The solar magnetic ... [more]

ESPOS Online Seminar: High-resolution spectroscopy of a minifilament eruption (Ioannis Kontogiannis)

ESPOS
Minifilaments are miniature versions of filaments, first observed in H-alpha filtergrams of quiet Sun. Recent studies have showcased their association with small-scale eruptive events, highlighting ... [more]

ESPOS Online Seminar: Forecasting solar flares with a new topological parameter and a supervised machine-learning method (Luca Giovannelli)

ESPOS
Solar flares originate from active regions (ARs) hosting complex and strong bipolar magnetic fluxes. Forecasting the probability of an AR to flare and defining reliable precursors of intense flares ... [more]

ESPOS Seminar: Test-particle simulations at tearing coronal null-point current sheets (Ross Pallister)

ESPOS
Magnetic reconnection is widely accepted to be a major contributor to nonthermal particle acceleration in the solar atmosphere. We investigate particle acceleration in two evolving field geometries ... [more]

ESPOS Seminar: Role of Heating-Cooling Misbalance on the Phase Shift of Propagating Slow Waves in Non-adiabatic Solar Coronal Loops (Abhinav Prasad)

ESPOS
Invoking the effects of thermal conductivity, compressive, viscosity, radiative losses, and heating-cooling misbalance, we derive the new general dispersion relation for the propagating slow MHD waves ... [more]

ESPOS Seminar: Formation and disappearance of a penumbra: Recent results (Mariarita Murabito)

ESPOS
The physical conditions resulting in the formation and disappearance of penumbral regions are poorly understood. We investigated these conditions by using high-resolution spectropolarimetric ... [more]

ESPOS Seminar: On the Differences in the Periodic Behavior of Magnetic Helicity Flux in Flaring Active Regions (Szabolcs Soós)

ESPOS
Observational precursors of large solar flares provide a basis for future operational systems for forecasting. We studied the evolution of the normalized emergence (EM), shearing (SH), and total (T) ... [more]

ESPOS Seminar: Small-scale MHD waves in the solar chromosphere with ALMA (Juan Camilo Guevara Gómez)

ESPOS

Validation of a wave heated 3D MHD coronal-wind model using Polarized Brightness and EUV observations

ESPOS

ESPOS Seminar: MHD wave propagation asymmetric solar waveguides (Noémi Kinga Zsámberger)

ESPOS
The analytical and numerical modelling of the behaviour of magnetohydrodynamic (MHD) waves in various magnetic geometries is a constantly evolving, active area of research within the field of solar ... [more]
Plasmoid-mediated fast magnetic reconnection plays a fundamental role in driving explosive dynamics and heating in the solar atmosphere, but relatively little is known about how it develops in ... [more]
The solar corona temperature is maintained to more than 1 MK. One of the main theories of the coronal formation (Parker 1988) suggests that the energy is dissipated into the corona through a high ... [more]

ESPOS - DKIST's view of quiet photospheric magnetism and application of neural networks to the characterisation of Stokes profiles (R. Campbell)

ESPOS
A new era of solar physics commences with observations of the quiet Sun using the 4-metre Daniel K. Inouye Solar Telescope/Visible Spectropolarimeter (DKIST/ViSP). We present full-Stokes observations ... [more]

ESPOS -Data-driven mode l of temporal evolution of the solar Mg II h and k profiles over the solar cycle (J. Koza)

ESPOS
The solar radiation in the cores of the Mg II h & k spectral lines strongly correlates with solar magnetic activity and global variations of magnetic fields with the solar cycle. This work provides a ... [more]

ESPOS - Deciphering solar coronal heating: Energizing small-scale loops through surface convection (D. Nóbrega-Siverio)

ESPOS
The solar atmosphere is filled with clusters of hot small-scale loops commonly known as Coronal Bright Points (CBPs). These ubiquitous structures stand out in the Sun by their strong X-ray and/or ... [more]

ESPOS - Thoughts on measuring elemental abundances in the solar atmosphere (G. Del Zanna)

ESPOS
I briefly review some methods and measurements of elemental abundances in the solar atmosphere, with emphasis on the transition region and corona. Some limitations in the methods, in the modeling of ... [more]

ESPOS - An overview of last October's SST-SolO observational campaign (S. Danilovic)

ESPOS
We present the results of coordinated observations of the Swedish 1-m Solar Telescope with Solar Orbiter that took place from October 12th to 26th 2023. The campaign resulted in 7 datasets of various ... [more]

ESPOS - Detection and in-depth analyses of quiet-Sun IRIS Bright Points (Llŷr Dafydd Humphries)

ESPOS
Observations of small-scale brightenings in the low solar atmosphere can provide valuable constraints on possible heating and heat transport mechanisms. We present a method for the detection and ... [more]

ESPOS -Automatic Identification and Tracking of Sunspots (Charlotte Proverbs)

ESPOS
It is well understood that the dynamics of sunspots lead to energy being transferred to the solar atmosphere and stored in the coronal magnetic field. This provides a surplus of energy that may be ... [more]
Go to Editor View