TIME EVOLUTION AND MORPHOLOGICAL-CHARACTERISTICS OF WHITE-LIGHT FLAREON 18 JANUARY 1989

Some properties of the white light flare (WLF) that occurred on 18 Jan uary 1989 are presented. The flare consisted of 7 patched-shape kernel s, with sizes (1.5 similar to 4) 10(17) cm(2). The lifetimes of the ke rnels were from several minutes to more than 40 minutes. The initial b right points of the WLF kernels originated between the umbra and penum bra in penumbra fibrils, between penumbra fibrils and the photosphere, or on the photosphere and light bridge. These kernels appeared 2 to 3 minutes after H alpha flares, and reached their maxima respectively b efore the first maximum and 1 to 2 minutes before the second maximum o f the H alpha flare, and disappeared slowly before the disappearance o f the H alpha flare. The direction and size of material motion in the kernels are different. The precur sors of the WLF are similar to those of ordinary flares. The magnetic pattern of the photosphere in the ac tive region is in delta- structure, and the kernels lie at or near the changing magnetic neutral lines. The small longitudinal field gradien t may be constrained by the small transverse field on the photosphere. The flare exhibited both temporal and spatial properties in the cente r reversal and line-width of H alpha profiles, and has characteristics of both class I and II. Thus it may be a mixed-class white light flar e.