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arXiv · 1109.3565

The Velocity Distribution of Solar Photospheric Magnetic Bright Points

Peter H. Keys·Mihalis Mathioudakis·David B. Jess·Sergiy Shelyag·Philip J. Crockett·Damian J. Christian·Francis P. Keenan
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Abstract

We use high spatial resolution observations and numerical simulations to study the velocity distribution of solar photospheric magnetic bright points. The observations were obtained with the Rapid Oscillations in the Solar Atmosphere instrument at the Dunn Solar Telescope, while the numerical simulations were undertaken with the MURaM code for average magnetic fields of 200 G and 400 G. We implemented an automated bright point detection and tracking algorithm on the dataset, and studied the subsequent velocity characteristics of over 6000 structures, finding an average velocity of approximately 1 km/s, with maximum values of 7 km/s. Furthermore, merging magnetic bright points were found to have considerably higher velocities, and significantly longer lifetimes, than isolated structures. By implementing a new and novel technique, we were able to estimate the background magnetic flux of our observational data, which is consistent with a field strength of 400 G.

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Peter H. Keys, Mihalis Mathioudakis, David B. Jess, Sergiy Shelyag, Philip J. Crockett, Damian J. Christian, Francis P. Keenan. 2011-09-16. The Velocity Distribution of Solar Photospheric Magnetic Bright Points. https://doi.org/10.1088/2041-8205%2F740%2F2%2Fl40

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