SOI/MDI Measurements of Horizontal Flows in the South Polar Region of the Sun by Correlation Tracking and Doppler Shifts

Session 69 - The Solar Dynamo and Helioseismology.
Display session, Thursday, June 13
Tripp Commons,

[69.13] SOI/MDI Measurements of Horizontal Flows in the South Polar Region of the Sun by Correlation Tracking and Doppler Shifts

G. Simon (Air Force Phillips Lab, AFMC, NSO), Z. Frank, N. Hurlburt, C. Schrijver, R. Shine, T. Tarbell, A. Title (Lockheed Martin Solar and Astrophysics Lab), C. DeForest (CSSA, Stanford Univ.)

On 7 March 1996, the SOHO spacecraft was offset from its usual disk center pointing for an 11-hour observation of the South Polar region. MDI took a continuous time series of high resolution longitudinal magnetograms during this period, in support of the SOHO-wide Joint Observing Program on polar plumes. It also ran several hours each of two other programs: one to map the horizontal flows near the pole by correlation tracking and Doppler shifts, and another to study wave propagation (e.g., by time-distance helioseismology) at these high latitudes. In this poster we present preliminary results from the first program. Both techniques yield measurements of the differential rotation profile near the pole and of horizontal flows of supergranulation. These results are compared with each other and with corresponding measurements in low latitudes. The location of magnetic features in the horizontal flows is also shown.

The SOI/MDI program is supported by NASA grant NAG5-3077.

Program listing for Thursday