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Session 1 - Chromosphere, Corona, Flares.
Display session, Friday, June 27
Ballroom B, Chair: Charles Kankelborg

[1.01] Recent Perplexing Behavior in Solar Activity Indices

J. C. LoPresto (Edinboro University of PA)

Calcium K and Halpha and SOHO He II UV plage and sunspot ara have been monitored using images on the INTERNET since November of 1992. The purpose of the project is to determine the degree of correlation between changing plage area and solar irradiance changes (also obtained via the INTERNET). Also the project provides a low cost process to involve undergraduates in astronomy research.

When using weighted weekly averages for both spot Halpha plage pixel counts, we see the expected decline from the last maximum. The activity continues to decline, or at best, has flattened out over the past several months. In contrast, the K-line plage pixel count from both Big Bear and Sacramento Peak show an upswing since mid-1995 or earlier. The k2 measurments from both Kitt Peak and Sacramento Peak are in general agreement with the spot and Halpha behavior, indicating wer are in, or barely passed minimum.

Images high in the chromosphere, detailing the magnetic network, may be more senstive to smaller field changes. This might be a partial explanation for the earlier upswing in K line and He 304 activity, which are receiving radiation near or at the top of the chromosphere.

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