Outputs (76)

The Sun’s Non-Potential Corona over Solar Cycle 24 (2024)
Journal Article
Yeates, A. R. (2024). The Sun’s Non-Potential Corona over Solar Cycle 24. Solar Physics, 299(6), Article 83. https://doi.org/10.1007/s11207-024-02328-5

The global magnetic field in the solar corona is known to contain free magnetic energy and magnetic helicity above that of a current-free (potential) state. But the strength of this non-potentiality and its evolution over the solar cycle remain uncer... Read More about The Sun’s Non-Potential Corona over Solar Cycle 24.

Transition to a weaker Sun: Changes in the solar atmosphere during the decay of the Modern Maximum (2024)
Journal Article
Mursula, K., Pevtsov, A. A., Asikainen, T., Tähtinen, I., & Yeates, A. R. (2024). Transition to a weaker Sun: Changes in the solar atmosphere during the decay of the Modern Maximum. Astronomy & Astrophysics, 685, Article A170. https://doi.org/10.1051/0004-6361/202449231

Context. The Sun experienced a period of unprecedented activity during the 20th century, now called the Modern Maximum (MM). The decay of the MM after its maximum in cycle 19 has changed the Sun, the heliosphere, and the planetary environments in man... Read More about Transition to a weaker Sun: Changes in the solar atmosphere during the decay of the Modern Maximum.

A Near-half-century Simulation of the Solar Corona (2024)
Journal Article
Aslanyan, V., Meyer, K. A., Scott, R. B., & Yeates, A. R. (2024). A Near-half-century Simulation of the Solar Corona. Astrophysical Journal Letters, 961(1), Article L3. https://doi.org/10.3847/2041-8213/ad1934

We present an overview of results from a magnetofrictional model of the entire solar corona over a period of 47 yr. The simulation self-consistently reproduces decades of solar phenomena, varying in duration between rapid eruptions and the long-term... Read More about A Near-half-century Simulation of the Solar Corona.

Computation of Winding-Based Magnetic Helicity and Magnetic Winding Density for SHARP Magnetograms in Spherical Coordinates (2023)
Journal Article
Xiao, D., Prior, C. B., & Yeates, A. R. (2023). Computation of Winding-Based Magnetic Helicity and Magnetic Winding Density for SHARP Magnetograms in Spherical Coordinates. Solar Physics, 298(10), Article 116. https://doi.org/10.1007/s11207-023-02211-9

Magnetic helicity has been used widely in the analysis and modelling of solar active regions. However, it is difficult to evaluate and interpret helicity in spherical geometry since coronal magnetic fields are rooted in the photosphere and helicity i... Read More about Computation of Winding-Based Magnetic Helicity and Magnetic Winding Density for SHARP Magnetograms in Spherical Coordinates.

Eruptivity Criteria for Solar Coronal Flux Ropes in Magnetohydrodynamic and Magnetofrictional Models (2023)
Journal Article
Rice, O. E. K., & Yeates, A. R. (2023). Eruptivity Criteria for Solar Coronal Flux Ropes in Magnetohydrodynamic and Magnetofrictional Models. Astrophysical Journal, 955(2), Article 114. https://doi.org/10.3847/1538-4357/acefc1

We investigate which scalar quantity or quantities can best predict the loss of equilibrium and subsequent eruption of magnetic flux ropes in the solar corona. Our models are initialized with a potential magnetic arcade, which is then evolved by mean... Read More about Eruptivity Criteria for Solar Coronal Flux Ropes in Magnetohydrodynamic and Magnetofrictional Models.

Spherical winding and helicity (2023)
Journal Article
Xiao, D., Prior, C., & Yeates, A. (2023). Spherical winding and helicity. Journal of Physics A: Mathematical and Theoretical, 56(20), Article 205201. https://doi.org/10.1088/1751-8121/accc17

In ideal magnetohydrodynamics, magnetic helicity is a conserved dynamical quantity and a topological invariant closely related to Gauss linking numbers. However, for open magnetic fields with non-zero boundary components, the latter geometrical inter... Read More about Spherical winding and helicity.

Surface Flux Transport on the Sun (2023)
Journal Article
Yeates, A., Cheung, M., Jiang, J., Petrovay, K., & Wang, Y. (2023). Surface Flux Transport on the Sun. Space Science Reviews, https://doi.org/10.1007/s11214-023-00978-8

We review the surface flux transport model for the evolution of magnetic flux patterns on the Sun’s surface. Our underlying motivation is to understand the model’s prediction of the polar field (or axial dipole) strength at the end of the solar cycle... Read More about Surface Flux Transport on the Sun.

Automated driving for global non-potential simulations of the solar corona (2022)
Journal Article
Yeates, A., & Bhowmik, P. (2022). Automated driving for global non-potential simulations of the solar corona. Astrophysical Journal, 935(1), Article 13. https://doi.org/10.3847/1538-4357/ac7de4

We describe a new automated technique for active region emergence in coronal magnetic field models, based on the inversion of the electric field locally from a single line-of-sight magnetogram for each region. The technique preserves the arbitrary sh... Read More about Automated driving for global non-potential simulations of the solar corona.

Eruptivity Criteria for Two-dimensional Magnetic Flux Ropes in the Solar Corona (2022)
Journal Article
Rice, O. E., & Yeates, A. R. (2022). Eruptivity Criteria for Two-dimensional Magnetic Flux Ropes in the Solar Corona. Frontiers in Astronomy and Space Sciences, 9, Article 849135. https://doi.org/10.3389/fspas.2022.849135

We apply the magneto-frictional approach to investigate which quantity or quantities can best predict the loss of equilibrium of a translationally-invariant magnetic flux rope. The flux rope is produced self-consistently by flux cancellation combined... Read More about Eruptivity Criteria for Two-dimensional Magnetic Flux Ropes in the Solar Corona.

Exploring the Origin of Stealth Coronal Mass Ejections with Magnetofrictional Simulations (2022)
Journal Article
Bhowmik, P., Yeates, A., & Rice, O. (2022). Exploring the Origin of Stealth Coronal Mass Ejections with Magnetofrictional Simulations. Solar Physics, 297(3), Article 41. https://doi.org/10.1007/s11207-022-01974-x

Coronal mass ejections (CMEs) – among the most energetic events originating from the Sun – can cause significant and sudden disruption to the magnetic and particulate environment of the heliosphere. Thus, in the current era of space-based technologie... Read More about Exploring the Origin of Stealth Coronal Mass Ejections with Magnetofrictional Simulations.