On physical properties of solar spicules

✍ Scribed by V. A. Krat; T. V. Krat

• Publisher: Springer
• Year: 1971
• Tongue: English
• Weight: 949 KB
• Volume: 17
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00150038

✦ Synopsis

New observations of solar spicules at Pulkovo, made simultaneously in 4 spectral regions, are described. The profiles of the Ha, D3, Hfl, H and K lines were derived for 23 spicules.

The spicules occur usually in narrow bundles and can be resolved into separate objects only due to a dispersion of radial velocities inside the bundle. The spicules in D3 are diffuse with faint interspicular emission.

The emission of hydrogen, helium and CaII originate in different parts of spicules with different radial and 'turbulent' velocities. The core of a spicule with Can emission is a narrow rope several tens of km in diameter for the normal section. The optical thickness of a spicule in Hc~ is approximately 1.0 and the atomic density varies from 1011 to 1012 cm -8.

The helium emission in spicules seems to be produced by different mechanisms, one of them being the external radiation of corona and subcoronal matter.

The model of a solar spicule is discussed.