X-ray emission associated with filament activity

Abstract

The temporal and spatial relationships of activated filaments, soft X-ray production, and H-alpha flares are investigated. The events chosen for study are from a sample of 114 hours of the very best, high-resolution H-alpha records of active regions gleaned from about 150 days of observations of active regions by Big Bear Solar Observatory, all with simultaneous mapping X-ray heliometer coverage. In the final data set, 20 flares are chosen for detailed study (10 significant flares and 10 smaller flarelike events). The data are examined for preflare filament activation and preflare X-ray enhancements with a view to discover a link between the two phenomena. To the limits set by the data, no convincing evidence for consistent preflare effects in H-alpha or X-rays is found. Aside from the 'disparition brusque', it seems clear that filament activity is not directly responsible for any dramatic effects in X-rays, and even there, the enhancement comes after the filament has disappeared.