A technique for timescale analysis of spectral lags performed directly in the time domain is developed. Simulation studies are made to compare the time domain t
87 stars in the NGC 6913 field with both UBV and Vilnius photometry are selected to be the sample. The membership probability of the stars is greater than 50%.
<正>We reported recently some rapid changes of sunspot structure in white-light(WL) associated with major flares.We extend the study to smaller events and prese