Ultraviolet spectra from the “Copernicus” satellite of the Wolf-Rayet star HD 50896 (Johnson, 1978; Cassinelli and Rumpl, 1982) show several P-Cygni profiles whose emission component has a larger equivalent width than the absorption component (see Figure 1). for lines with saturated absorption components, such as the N V (λλ1239–1243) line, the excess emission is due to thermal emission from the wind. However, for unsaturated lines which are due to scattering, such as the P V (λλ1118–1128) and O VI (λλ1032–1038) lines, the excess emission suggests that the scattering is not spherically symmetric.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.