36 citations · 218 across the 23 of their papers we have counts for
25 papers
Three-dimensional magnetic reconnection in unipolar regions. A case study of coronal bright points in the Sun
D. Nóbrega-Siverio, F. Moreno-Insertis, A. S. H. To
Magnetic reconnection is a fundamental mechanism underlying the heating and a wide variety of eruptive phenomena in the solar atmosphere; however, characterizing its 3D aspects rem…
Active nests at solar maximum: How nested flux emergence dominated flaring activity and structured the heliosphere
Adam J. Finley, Allan Sacha Brun, Antoine Strugarek +5
Multi-viewpoint observations from near-Earth satellites and ESA's Solar Orbiter enable a global view of the Sun. This continuous coverage is essential for characterising active nes…
Nonthermal line broadening at solar flare footpoints is primarily field-aligned
Andy S. H. To, Alexander J. B. Russell
Magnetic reconnection powers solar and stellar flares, but a full understanding of how the released energy is transported and converted within the solar atmosphere remains elusive.…
Signs of Sulphur fractionation under high magnetic field strength
Dominik Orlovskij, Andy S. H. To, David M. Long
Sulphur, with a first ionisation potential (FIP) of 10.36 eV, lies at the boundary between low- and high-FIP elements, making it particularly sensitive to fractionation processes i…
Chromospheric dynamics and turbulence regulate the solar FIP effect
Andy S. H. To, J. Martin Laming, Jeffrey Reep +1
Elemental abundance variations in the solar corona, commonly characterised by First Ionisation Potential (FIP) bias, provide crucial diagnostics of chromospheric processes. The pon…
Comparing First Ionisation Potential bias diagnostics in the solar atmosphere
Kristena D. Spruksta, David M. Long, Andy S. H. To
Plasma composition in the solar atmosphere differs between the photosphere and corona, producing an observable difference in elemental abundance known as the FIP effect. The FIP ef…
Sulfur fractionation in coronal plumes as observed by Solar Orbiter/SPICE
Slimane Mzerguat, Miho Janvier, Eric Buchlin +4
Coronal plumes are bright, narrow structures rooted in coronal holes that contribute to the solar wind. Their composition, particularly elemental fractionation as a function of fir…
Dynamic modeling of coronal abundances during flares on M-dwarf stars
David H. Brooks, Jeffrey W. Reep, Andy S. H. To +2
Solar atmospheric elemental abundances are now known to vary both in space and time. Dynamic modeling of these changes is therefore necessary to improve the accuracy of radiative h…
Radiative hydrodynamic simulations of FIP fractionation in solar flares
Jeffrey W. Reep, Luke Fushimi Benavitz, Andy S. H. To +5
Elemental abundances in solar flares are observed to vary both spatially and temporally, but the underlying mechanisms remain poorly understood. There is an interplay between advec…
Systematic non-thermal velocity increase preceding soft X-ray flare onset: A large-scale Hinode/EIS study
Andy S. H. To, Abigail Burden, Deborah Baker +12
Non-thermal velocities, derived from spectral line broadening, can provide crucial insights into plasma dynamics before and during solar flares. To systematically study the pre-fla…
Spatiotemporal Low FIP Abundance: A Catalyst for Coronal Condensation
Luke Fushimi Benavitz, Jeffrey W. Reep, Lucas A. Tarr +1
Radiative losses play a critical role in the cooling of plasmas. When chromospheric plasma is sufficiently heated, it can flow into coronal loops which subsequently cool down due t…
Spatially Resolved Plasma Composition Evolution in a Solar Flare -- The Effect of Reconnection Outflow
Andy S. H. To, David H. Brooks, Shinsuke Imada +6
Solar flares exhibit complex variations in elemental abundances compared to photospheric values. We examine the spatial and temporal evolution of coronal abundances in the X8.2 fla…
Searching for evidence of subchromospheric magnetic reconnection on the Sun
D. Baker, L. van Driel-Gesztelyi, A. W. James +13
Within the coronae of stars, abundances of those elements with low first ionization potential (FIP) often differ from their photospheric values. The coronae of the Sun and solar-ty…
Observation of Alfvén Wave Reflection in the Solar Chromosphere: Ponderomotive Force and First Ionization Potential Effect
Mariarita Murabito, Marco Stangalini, J. Martin Laming +7
We investigate the propagation of Alfvén waves in the solar chromosphere, distinguishing between upward and downward propagating waves. We find clear evidence for the reflection of…
Identifying plasma fractionation processes in the chromosphere using IRIS
David M. Long, Deborah Baker, Andy S. H. To +7
The composition of the solar corona differs from that of the photosphere, with the plasma thought to fractionate in the solar chromosphere according to the First Ionisation Potenti…
The Merging of a Coronal Dimming and the Southern Polar Coronal Hole
Nawin Ngampoopun, David M. Long, Deborah Baker +4
We report on the merging between the southern polar coronal hole and an adjacent coronal dimming induced by a coronal mass ejection on 2022 March 18, resulting in the merged region…
Slow Solar Wind Connection Science during Solar Orbiter's First Close Perihelion Passage
Stephanie L. Yardley, Christopher J. Owen, David M. Long +76
The Slow Solar Wind Connection Solar Orbiter Observing Plan (Slow Wind SOOP) was developed to utilise the extensive suite of remote sensing and in situ instruments on board the ESA…
Understanding the Relationship between Solar Coronal Abundances and F10.7 cm Radio Emission
Andy S. H. To, Alexander W. James, T. S. Bastian +7
Sun-as-a-star coronal plasma composition, derived from full-Sun spectra, and the F10.7 radio flux (2.8 GHz) have been shown to be highly correlated (r = 0.88) during solar cycle 24…
Observational Evidence of S-Web Source of the Slow Solar Wind
D. Baker, P. Demoulin, S. L. Yardley +25
From 2022 March 18-21, active region (AR) 12967 was tracked simultaneously by Solar Orbiter (SO) at 0.35 au and Hinode/EIS at Earth. During this period, strong blue-shifted plasma…
What determines active region coronal plasma composition?
Teodora Mihailescu, Deborah Baker, Lucie M. Green +4
The chemical composition of the solar corona is different from that of the solar photosphere, with the strongest variation being observed in active regions (ARs). Using data from t…
Evolution of Plasma Composition in an Eruptive Flux Rope
Deborah Baker, Lucie M. Green, David H. Brooks +8
Magnetic flux ropes are bundles of twisted magnetic field enveloping a central axis. They harbor free magnetic energy and can be progenitors of coronal mass ejections (CMEs), but i…
The Evolution of Plasma Composition During a Solar Flare
Andy S. H. To, David M. Long, Deborah Baker +4
We analyse the coronal elemental abundances during a small flare using Hinode/EIS observations. Compared to the pre-flare elemental abundances, we observed a strong increase in cor…
Alfvenic Perturbations in a Sunspot Chromosphere Linked to Fractionated Plasma in the Corona
D. Baker, M. Stangalini, G. Valori +7
In this study, we investigate the spatial distribution of highly varying plasma composition around one of the largest sunspots of solar cycle 24. Observations of the photosphere, c…
Spectropolarimetric Fluctuations in a Sunspot Chromosphere
M. Stangalini, D. Baker, G. Valori +8
The instrumental advances made in this new era of 4-meter class solar telescopes with unmatched spectropolarimetric accuracy and sensitivity, will enable the study of chromospheric…