Solar Physics Division Meeting 2000, June 19-22
Session 2. Corona, Solar Wind, Flares, CMEs, Solar-stellar, Instrumentation, Other
Display, Chair: J. Krall, Monday-Thursday, June 19, 2000, 8:00am-6:00pm, Forum Ballroom

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[2.25] Variation of the Large-Scale Coronal Temperature at Mid-to-High Latitudes over 1.5 Solar Cycles

R. C. Altrock (Air Force Research Lab. at NSO/SP)

Observations of the forbidden coronal lines Fe XIV 530.3 nm and Fe X 637.4 nm obtained at the National Solar Observatory at Sacramento Peak are used to determine the variation of coronal temperature at latitudes above 30 degrees outside of active regions during cycles 22 and 23. A pattern, which is symmetric about solar maximum during cycle 22 and consistent between the northern and southern hemisphere, is seen. Beginning near solar minimum in 1985, the temperature above 60 degrees latitude is at a minimum value, varying from about 1.3 MK near the poles to about 1.5 MK near 60 degrees. Near the time that the "Rush-to-the-Poles" begins in 1987, the high-latitude temperature increases abruptly, reaching values of 1.7 MK at the North pole and 1.6 MK at the South pole in 1989. After 1990, the process reverses, and temperatures at the poles are below 1.3 MK by 1995. The rise to the maximum of cycle 23 will be compared with that of cycle 22.


The author(s) of this abstract have provided an email address for comments about the abstract: altrock@sunspot.noao.edu

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