Broad Hα wings in Nebulae around Evolved Stars and in Young Planetary Nebulae
نویسنده
چکیده
Eleven objects that have been reported as proto-planetary nebula or as young planetary nebulae that show very extended Hα wings are presented. The extension of these wings is larger than 800 km s . Data for two symbiotic stars that show this same characteristic is also presented. Raman scattering is the mechanism that best explains the wings in 10 of the PNe and in the 2 symbiotic stars. In the PN IRAS 20462+3416 the wing profile can be explained by very intense stellar wind. Subject headings: ISM:planetary nebulae:–binaries:symbiotic–scattering– stars:massloss–stars: AGB and post-AGB Line: profiles
منابع مشابه
ar X iv : a st ro - p h / 99 11 42 2 v 1 2 3 N ov 1 99 9 Submitted to ApJ Letters Broad H α Wing Formation in the Planetary Nebula IC 4997
The young and compact planetary nebula IC 4997 is known to exhibit very broad wings with a width exceeding 5000 km s −1 around Hα. We propose that the broad wings are formed through Rayleigh-Raman scattering involving atomic hydrogen, by which Lyβ photons with a velocity width of a few 10 2 km s −1 are converted to optical photons and fill the Hα broad wing region. The conversion efficiency rea...
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