All Outputs (43)

Magnetic Structures at the Boundary of the Closed Corona: A Semi-automated Study of S-Web Morphology (2019)
Journal Article
Scott, R. B., Pontin, D. I., & Wyper, P. F. (2019). Magnetic Structures at the Boundary of the Closed Corona: A Semi-automated Study of S-Web Morphology. Astrophysical Journal, 882(2), Article 125. https://doi.org/10.3847/1538-4357/ab364a

Interchange reconnection is thought to play an important role in driving the dynamics of the slow solar wind. To understand the details of this process, it is important to catalog the various magnetic structures that are present at the boundary betwe... Read More about Magnetic Structures at the Boundary of the Closed Corona: A Semi-automated Study of S-Web Morphology.

Exploring Flaring Behaviour on Low Mass Stars, Solar-type Stars and the Sun (2019)
Journal Article
Doyle, L., Ramsay, G., Doyle, J., Wyper, P., Scullion, E., Wu, K., & McLaughlin, J. (2019). Exploring Flaring Behaviour on Low Mass Stars, Solar-type Stars and the Sun. Proceedings of the International Astronomical Union, 15(S354), 384-319. https://doi.org/10.1017/s1743921319009980

We report on our project to study the activity in both the Sun and low mass stars. Utilising high cadence, Hα observations of a filament eruption made using the CRISP spectropolarimeter mounted on the Swedish Solar Telescope has allowed us to determi... Read More about Exploring Flaring Behaviour on Low Mass Stars, Solar-type Stars and the Sun.

Multiwavelength Study of Equatorial Coronal-hole Jets (2019)
Journal Article
Kumar, P., Karpen, J. T., Antiochos, S. K., Wyper, P. F., DeVore, C. R., & DeForest, C. E. (2019). Multiwavelength Study of Equatorial Coronal-hole Jets. Astrophysical Journal, 873(1), Article 93. https://doi.org/10.3847/1538-4357/ab04af

Jets (transient/collimated plasma ejections) occur frequently throughout the solar corona and contribute mass/energy to the corona and solar wind. By combining numerical simulations and high-resolution observations, we have made substantial progress... Read More about Multiwavelength Study of Equatorial Coronal-hole Jets.

Proton acceleration at tearing coronal null-point current sheets (2019)
Journal Article
Pallister, R., Pontin, D., & Wyper, P. (2019). Proton acceleration at tearing coronal null-point current sheets. Astronomy & Astrophysics, 622, Article A207. https://doi.org/10.1051/0004-6361/201834284

Context. Non-thermal particle acceleration in the solar corona is thought to constitute a substantial part of the energy budget of explosive events such as solar flares. One well-established mechanism of non-thermal acceleration is directly via field... Read More about Proton acceleration at tearing coronal null-point current sheets.

Magnetic Structures at the Boundary of the Closed Corona: Interpretation of S-Web Arcs (2018)
Journal Article
Scott, R. B., Pontin, D. I., Yeates, A. R., Wyper, P. F., & Higginson, A. K. (2018). Magnetic Structures at the Boundary of the Closed Corona: Interpretation of S-Web Arcs. Astrophysical Journal, 869(1), Article 60. https://doi.org/10.3847/1538-4357/aaed2b

The topology of coronal magnetic fields near the open-closed magnetic flux boundary is important to the the process of interchange reconnection, whereby plasma is exchanged between open and closed flux domains. Maps of the magnetic squashing factor i... Read More about Magnetic Structures at the Boundary of the Closed Corona: Interpretation of S-Web Arcs.

A Model for Coronal Hole Bright Points and Jets Due to Moving Magnetic Elements (2018)
Journal Article
Wyper, P., DeVore, C., Karpen, J., Antiochos, S., & Yeates, A. (2018). A Model for Coronal Hole Bright Points and Jets Due to Moving Magnetic Elements. Astrophysical Journal, 864(2), Article 165. https://doi.org/10.3847/1538-4357/aad9f7

Coronal jets and bright points occur prolifically in predominantly unipolar magnetic regions, such as coronal holes (CHs), where they appear above minority-polarity intrusions. Intermittent low-level reconnection and explosive, high-energy-release re... Read More about A Model for Coronal Hole Bright Points and Jets Due to Moving Magnetic Elements.

Evidence for the Magnetic Breakout Model in an Equatorial Coronal-hole Jet (2018)
Journal Article
Kumar, P., Karpen, J. T., Antiochos, S. K., Wyper, P. F., DeVore, C. R., & DeForest, C. E. (2018). Evidence for the Magnetic Breakout Model in an Equatorial Coronal-hole Jet. Astrophysical Journal, 854(2), Article 155. https://doi.org/10.3847/1538-4357/aaab4f

Small, impulsive jets commonly occur throughout the solar corona, but are especially visible in coronal holes. Evidence is mounting that jets are part of a continuum of eruptions that extends to much larger coronal mass ejections and eruptive flares.... Read More about Evidence for the Magnetic Breakout Model in an Equatorial Coronal-hole Jet.

A Breakout Model for Solar Coronal Jets with Filaments (2018)
Journal Article
Wyper, P., DeVore, C., & Antiochos, S. (2018). A Breakout Model for Solar Coronal Jets with Filaments. Astrophysical Journal, 852(2), Article 98. https://doi.org/10.3847/1538-4357/aa9ffc

Recent observations have revealed that many solar coronal jets involve the eruption of miniature versions of large-scale filaments. Such "mini-filaments" are observed to form along the polarity inversion lines of strong, magnetically bipolar regions... Read More about A Breakout Model for Solar Coronal Jets with Filaments.

The Mechanism for the Energy Buildup Driving Solar Eruptive Events (2017)
Journal Article
Knizhnik, K., Antiochos, S., DeVore, C., & Wyper, P. (2017). The Mechanism for the Energy Buildup Driving Solar Eruptive Events. Astrophysical Journal, 851(1), Article L17. https://doi.org/10.3847/2041-8213/aa9e0a

The underlying origin of solar eruptive events (SEEs), ranging from giant coronal mass ejections to small coronal-hole jets, is that the lowest-lying magnetic flux in the Sun's corona undergoes continual buildup of stress and free energy. This magnet... Read More about The Mechanism for the Energy Buildup Driving Solar Eruptive Events.

Formation of Heliospheric Arcs of Slow Solar Wind (2017)
Journal Article
Higginson, A., Antiochos, S., DeVore, C., Wyper, P., & Zurbuchen, T. (2017). Formation of Heliospheric Arcs of Slow Solar Wind. Astrophysical Journal Letters, 840(1), Article L10. https://doi.org/10.3847/2041-8213/aa6d72

A major challenge in solar and heliospheric physics is understanding the origin and nature of the so-called slow solar wind. The Sun's atmosphere is divided into magnetically open regions, known as coronal holes, where the plasma streams out freely a... Read More about Formation of Heliospheric Arcs of Slow Solar Wind.

A universal model for solar eruptions (2017)
Journal Article
Wyper, P. F., Antiochos, S. K., & DeVore, C. R. (2017). A universal model for solar eruptions. Nature, 544(7651), 452-455. https://doi.org/10.1038/nature22050

Magnetically driven eruptions on the Sun, from stellar-scale coronal mass ejections to small-scale coronal X-ray and extreme-ultraviolet jets, have frequently been observed to involve the ejection of the highly stressed magnetic flux of a filament. T... Read More about A universal model for solar eruptions.

Dynamics of Coronal Hole Boundaries (2017)
Journal Article
Higginson, A., Antiochos, S., DeVore, C., Wyper, P., & Zurbuchen, T. (2017). Dynamics of Coronal Hole Boundaries. Astrophysical Journal, 837(2), Article 113. https://doi.org/10.3847/1538-4357/837/2/113

Remote and in situ observations strongly imply that the slow solar wind consists of plasma from the hot, closed-field corona that is released onto open magnetic field lines. The Separatrix Web theory for the slow wind proposes that photospheric motio... Read More about Dynamics of Coronal Hole Boundaries.

Three-Dimensional Simulations of Tearing and Intermittency in Coronal Jets (2016)
Journal Article
Wyper, P., DeVore, C., Karpen, J., & Lynch, B. (2016). Three-Dimensional Simulations of Tearing and Intermittency in Coronal Jets. Astrophysical Journal, 827(1), Article 4. https://doi.org/10.3847/0004-637x/827/1/4

Observations of coronal jets increasingly suggest that local fragmentation and intermittency play an important role in the dynamics of these events. In this work, we investigate this fragmentation in high-resolution simulations of jets in the closed-... Read More about Three-Dimensional Simulations of Tearing and Intermittency in Coronal Jets.

Simulations of Solar Jets Confined by Coronal Loops (2016)
Journal Article
Wyper, P., & DeVore, C. (2016). Simulations of Solar Jets Confined by Coronal Loops. Astrophysical Journal, 820(1), Article 77. https://doi.org/10.3847/0004-637x/820/1/77

Coronal jets are collimated, dynamic events that occur over a broad range of spatial scales in the solar corona. In the open magnetic field of coronal holes, jets form quasi-radial spires that can extend far out into the heliosphere, while in closed-... Read More about Simulations of Solar Jets Confined by Coronal Loops.

The Effect of Reconnection on the Structure of the Sun's Open-Closed Flux Boundary (2015)
Journal Article
Pontin, D., & Wyper, P. (2015). The Effect of Reconnection on the Structure of the Sun's Open-Closed Flux Boundary. Astrophysical Journal, 805(1), Article 39. https://doi.org/10.1088/0004-637x/805/1/39

Global magnetic field extrapolations are now revealing the huge complexity of the Sun's corona, and in particular the structure of the boundary between open and closed magnetic flux. Moreover, recent developments indicate that magnetic reconnection i... Read More about The Effect of Reconnection on the Structure of the Sun's Open-Closed Flux Boundary.

Quantifying three dimensional reconnection in fragmented current layers (2015)
Journal Article
Wyper, P., & Hesse, M. (2015). Quantifying three dimensional reconnection in fragmented current layers. Physics of Plasmas, 22(4), Article 042117. https://doi.org/10.1063/1.4918335

There is growing evidence that when magnetic reconnection occurs in high Lundquist number plasmas such as in the Solar Corona or the Earth's Magnetosphere it does so within a fragmented, rather than a smooth current layer. Within the extent of these... Read More about Quantifying three dimensional reconnection in fragmented current layers.

Dynamic topology and flux rope evolution during non-linear tearing of 3D null point current sheets (2014)
Journal Article
Wyper, P., & Pontin, D. (2014). Dynamic topology and flux rope evolution during non-linear tearing of 3D null point current sheets. Physics of Plasmas, 21(10), Article 102102. https://doi.org/10.1063/1.4896060

In this work, the dynamic magnetic field within a tearing-unstable three-dimensional current sheet about a magnetic null point is described in detail. We focus on the evolution of the magnetic null points and flux ropes that are formed during the tea... Read More about Dynamic topology and flux rope evolution during non-linear tearing of 3D null point current sheets.

Non-linear tearing of 3D null point current sheets (2014)
Journal Article
Wyper, P., & Pontin, D. (2014). Non-linear tearing of 3D null point current sheets. Physics of Plasmas, 21(8), Article 082114. https://doi.org/10.1063/1.4893149

The manner in which the rate of magnetic reconnection scales with the Lundquist number in realistic three-dimensional (3D) geometries is still an unsolved problem. It has been demonstrated that in 2D rapid non-linear tearing allows the reconnection r... Read More about Non-linear tearing of 3D null point current sheets.

Reconnection at three dimensional magnetic null points: Effect of current sheet asymmetry (2013)
Journal Article
Wyper, P., & Jain, R. (2013). Reconnection at three dimensional magnetic null points: Effect of current sheet asymmetry. Physics of Plasmas, 20(5), Article 052901. https://doi.org/10.1063/1.4804338

Asymmetric current sheets are likely to be prevalent in both astrophysical and laboratory plasmas with complex three dimensional (3D) magnetic topologies. This work presents kinematic analytical models for spine and fan reconnection at a radially sym... Read More about Reconnection at three dimensional magnetic null points: Effect of current sheet asymmetry.

Kelvin-Helmholtz instability in a current-vortex sheet at a 3D magnetic null (2013)
Journal Article
Wyper, P., & Pontin, D. (2013). Kelvin-Helmholtz instability in a current-vortex sheet at a 3D magnetic null. Physics of Plasmas, 20(3), Article 032117. https://doi.org/10.1063/1.4798516

We report here, for the first time, an observed instability of a Kelvin-Helmholtz nature occurring in a fully three-dimensional (3D) current-vortex sheet at the fan plane of a 3D magnetic null point. The current-vortex layer forms self-consistently i... Read More about Kelvin-Helmholtz instability in a current-vortex sheet at a 3D magnetic null.