Hostname: page-component-848d4c4894-ndmmz Total loading time: 0 Render date: 2024-05-21T09:59:08.621Z Has data issue: false hasContentIssue false

On some aspects of XUV spectroheliograms

Published online by Cambridge University Press:  14 August 2015

R. Tousey
Affiliation:
E.O. Hulburt Center for Space Research, U.S. Naval Research Laboratory, Washington, D.C., U.S.A.
G. D. Sandlin
Affiliation:
E.O. Hulburt Center for Space Research, U.S. Naval Research Laboratory, Washington, D.C., U.S.A.
J. D. Purcell
Affiliation:
E.O. Hulburt Center for Space Research, U.S. Naval Research Laboratory, Washington, D.C., U.S.A.

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

A comparison between XUV and Ca-K spectroheliograms for 9 dates from 1963 to 1967 showed an excellent correlation between plage intensities in Ca-K and He II 304 Å, except for plages near the limb and a few others. Around the limb all but the highest ionization XUV emission lines form a bright ring, usually weaker over the poles. This is an unresolved combination of the limb-brightened emission from the quiet corona and high chromosphere, and emission extending into the corona above plages located as much as several days from limb passage.

In Fe XV and XVI only the localized coronal emissions are observed; these vary in form and intensity from line to line. The 171–500 Å and white-light coronas, recorded on November 12, 1966, correlate well at low altitudes, but beyond 3′ the XUV corona becomes diffuse and without structure.

Type
Part V: Coronal and Interplanetary Structure of an Active Region
Copyright
Copyright © Reidel 1968 

References

Dodson-Prince, H., Hedeman, E.R. (1967) Annals of the IQSY. Google Scholar
Newkirk, G. Jr. (1967) Sky and Telescope, 33, 136.Google Scholar
Purcell, J.D., Tousey, R. (1961) Mém. Soc. R. Sc. Liège, 4, 274.Google Scholar
Purcell, J.D., Tousey, R., Koomen, M.J. (1967) in Space Research, VIII.Google Scholar
Smith, T.S. (1967) discussion at the meeting of the Amer. Astron. Soc., Boulder, Colo., Oct. 3, 1966.Google Scholar