The brightness of the helium D3line in the undisturbed chromosphere from eclipse observations

✍ Scribed by R. A. Gulyaev

• Publisher: Springer
• Year: 1975
• Tongue: English
• Weight: 907 KB
• Volume: 44
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00156844

✦ Synopsis

Slitless spectra of the chromosphere, observed cinematographically at the total solar eclipse of 10 July 1972, were reduced. The surface brightness distribution of the helium D3 line in the undisturbed chromosphere was obtained in agreement with results by other observers. The available eclipse data on the Dz absolute brightness was analysed by means of theoretical curves of growth. Intensity data by some observers were found to be certainly too high.

A trend was found that the D8 absolute brightness in the quiet chromosphere decreases with the increasing solar activity (sunspot number). This perhaps indicates a variation of the spicule number over the solar surface during a sunspot cycle.