Physical parameters of point-symmetric planetary nebulae
نویسندگان
چکیده
منابع مشابه
The Kinematics of Point - Symmetric Planetary Nebulae : Observational Evidence of Precessing Outflows Mart́ın
The discovery of collimated outflows associated to point-symmetric features in Planetary Nebulae has proliferated in recent years. The systematic variation of radial velocity that many of them show strongly suggests a uniform rotation or precession of the ejection direction. Although several physical processes have been invoked, the formation mechanism of precessing collimated outflows in PNe i...
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Planetary nebulae (PNe) can be used to trace intermediate and old stellar populations in galaxies and the intracluster medium out to approximately 20 Mpc. PNe can be easily identified with narrow-band surveys, and their chemical abundances and radial velocities can be measured with multi-slit or multi-fiber spectrographs. We briefly review what has been accomplished to date, and include tables ...
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ژورنال
عنوان ژورنال: Proceedings of the International Astronomical Union
سال: 2006
ISSN: 1743-9213,1743-9221
DOI: 10.1017/s1743921306004091