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Session 2 - Everything Else.
Display session, Friday, June 27
Ballroom C, Chair: Richard Canfield

[2.19] Measurements of Magnetic Element Dynamics in the Network

T. E. Berger, M. G. Löfdahl, R. A. Shine, A. M. Title (Lockheed-Martin, O/H1-12)

Statistical measurements of magnetic element speed, interaction frequency, and lifetime in an enhanced network region at disk center are presented. The primary dataset is a 70 min time series of G-band 4305 Å\ filtergrams taken at the 50 cm Swedish Vacuum Solar Telescope (SVST) on the island of La Palma, Spain. A second time series of 4686 Å\ wide-band continuum filtergrams, cospatial and simultaneous to within several milliseconds with the G-band images, is also studied. The field-of-view is near Sun center and includes a region of enhanced network activity with many G-band bright points. Both time series are corrected for seeing to very near the telescope diffraction limit by the technique of Phase Diverse Speckle (PDS) restoration (see accompanying poster by M. G. Löfdahl et al). We show destretched and space-time filtered movies of both the G-band and continuum images in two fields-of-view: a region of quiet granulation and the region of enhanced network activity. Within the network, local correlation tracking measurements on a 0\farcs4 grid show the RMS speed to be 778 m s^-1; outside the network the RMS speed is 1168 m s^-1. Corkflow simulations show that normal convective flow patterns (granulation and mesogranulation) are absent in the network. Magnetic elements move with modal and mean speeds of 100 m s^-1 and 815 m s^-1, respectively. The mean interaction frequency (time between either merging or splitting) is 220 s. The mean lifetime of tracked magnetic elements in the network is 9.33 min although 5% of the elements are tracked for the entire 70 min of the times series. This work was supported by NASA contracts NAS5-30386 at Stanford and NAS8-39747 and Independent Research Funds at Lockheed-Martin. MGL was supported by the Swedish Science Research Council.


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The author(s) of this abstract have provided an email address for comments about the abstract: berger@sag.space.lockheed.com

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