Spectro-polarimetric observation of the fine structureof a quiescent filament

Abstract

This paper presents the spectro-polarimetric measurements of a big quiescent filament observed by the MSDP mode of the THEMIS on August 24, 2000. The Hα, CaII 8542 and NaI D2 line profiles of a segment of the filament were obtained. By use of the Hα images with high spatial resolution, the two barb endpoints were identified. The parameters at the barbs' endpoints, including intensity, velocity and longitudinal magnetic field were measured. Using the data with high spatial resolution (0.16'' per pixel), we have found the following results. 1) There was mass motion at the barb endpoints in the chromosphere, the values and the directions of the mass motion at the barb endpoints change in several minutes. 2) The two barb endpoints are located between the majority polarities and the minority polarities.