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arXiv · 1002.3656

Spectroscopic Studies of Limb Spicules. I. Radial and Turbulent Velocities

Makiko Shoji·Takara Nishikawa·Reizaburo Kitai·Satoru Ueno
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Abstract

We made high-resolution spectroscopic observations of limb-spicules in H-alpha 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 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 and the Doppler-widths are 0.6 - 0.9 A. Non-thermal "macroturbulent" velocities of order 30 km/s are required to explain these width-values.

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Makiko Shoji, Takara Nishikawa, Reizaburo Kitai, Satoru Ueno. 2010-02-19. Spectroscopic Studies of Limb Spicules. I. Radial and Turbulent Velocities. https://doi.org/10.1093/pasj%2F62.4.927

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