The Lyman-alpha line in various solar features. I - Observations

Abstract

view Abstract Citations (58) References (18) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Lyman-Alpha Line in Various Solar Features. I. Observations Fontenla, J. ; Reichmann, E. J. ; Tandberg-Hanssen, E. Abstract The authors give an overview of the main features of the solar atmosphere as observed in the Lyα line by the Ultraviolet Spectrometer and Polarimeter on the SMM. The authors use high spectral and spatial resolution data as well as broad-band spectroheliograms to characterize the various features, and they present the values which theoretical models have to explain. It is shown that on the disk (quiet Sun and active regions) the central reversal of the line is highly variable in depth and frequently shifted, leading to asymmetric profiles. Observations above the limb reveal the appearance of a dynamic layer (cloud layer) overlying the limb. The authors present its Lyα profile and show that it can be responsible for distorting the background profile of the line and leading to the observed asymmetric profiles. Publication: The Astrophysical Journal Pub Date: June 1988 DOI: 10.1086/166392 Bibcode: 1988ApJ...329..464F Keywords: Lyman Alpha Radiation; Solar Activity; Solar Atmosphere; Solar Observatories; Solar Spectra; Ultraviolet Spectra; Energy Dissipation; Radiative Heat Transfer; Solar Corona; Solar Maximum Mission; Solar Physics; SUN: ACTIVITY; SUN: SPECTRA; ULTRAVIOLET: SPECTRA full text sources ADS |