Videos of Magnetohydrodynamics Simulations of Solar Atmosphere Wave Dynamics Generated by Solar Global Oscillating Eigenmodes
The solar atmosphere exhibits a diverse range of wave phenomena one of the earliest to be discovered was the five minute oscillation, the p-mode. The analysis of wave propagation in the solar atmosphere may be used as a diagnostic tool to measure the physical characteristics of the suns atmospheric layers.
The videos in this collection are the result of an investigation of the dynamics and propagation of waves which are generated by the solar global eigenmodes. We present the results of a series of hydrodynamic simulations of a realistic model of the solar atmosphere. With the objective of recreating atmospheric motions generated by global resonant oscillation the simulations use a driver which is spatially structured and extended in a sinusoidal profile across the computational model. The drivers perturb the region at 0.5Mm above the bottom boundary of the model and coincident with the temperature minimum. A combination of the VALIIIC and McWhirter solar atmospheres and coronal density profiles were used as the background equilibrium model in the simulations. We present the results of a study of synthetic photospheric oscillations for a magnetic field free model of the quiet sun. To carry out the simulations, we employed the MHD code, SMAUG (Sheffield MHD Accelerated Using GPUs).
See the reference at the Astronomy Abstracts Service. SMAUG paper at ADS
See the reference at the Astronomy Abstracts Service. SAC paper at ADS
Each video shows the value of the vertical component of the plasma velocity (z-component) along different slices through the simulation box. The scale shows the velocity value in m/s. The green vectors show the velocity directions along a single slice through the simulation. The green surface at a height of 3.5Mm is the 2MK temperature isosurface. The simulation box is 4Mmx4Mm along the base and the height of the box is 5.7Mm. The driver for the simulations is located at a height of 0.5Mm.
Each video is labelled using 3 numbers. The first number is the driver period in seconds. The following 2 integers are each of the mode indices for the x and y direction respectively.
Our results show that the amount of energy propagated into the solar atmosphere is consistent with a model of solar global oscillations described using the Klein-Gordon equation. The calculated results indicate a power law consistent with observational results obtained using SDO AIA Ireland2015 .
Ireland, J.; McAteer, R. T. J.; Inglis, A. R., Coronal Fourier Power Spectra: Implications for Coronal Seismology and Coronal Heating, The Astrophysical Journal, Volume 798, Issue 1, article id. 1, 12 pp. (2015).DigitalMediaRepository
Link to videos (google)
We acknowledge the support of the University of Sheffield and Corporate Information and Computing Services for the provision of its High Performance Computing facility that was used to generate this data set.