We made high-resolution spectroscopic observations of limb-spicules in Hα using the Vertical Spectrograph of Domeless Solar Telescope at Hida Observatory. While more than half of the observed spicules have Gaussian line-profiles, some spicules have distinctly asymmetric profiles which can be fitted with two Gaussian components. The faster of these components has radial velocities of 10 - 40 km s-1 and Doppler-widths of about 0.4 A which suggest that it is from a single spicule oriented nearly along the line-of-sight. Profiles of the slower components and the single-Gaussian type show very similar characteristics. Their radial velocities are less than 10 km s-1 and the Doppler-widths are 0.6 - 0.9 A. Non-thermal ''macroturbulent'' velocities of order 30 km s-1 are required to explain these width-values.
Authors: Shoji, M., Nishikawa, T., Kitai, R., Ueno, S.
Publication Status: PASJ (in press)
Last Modified: 2010-02-22 09:07