Results 21 to 30 of about 172,889 (233)
Galactic Planetary Nebulae as Probes of Radial Metallicity Gradients and Other Abundance Patterns [PDF]
Astrophysical Journal, 2018 We use planetary nebulae (PNe) as probes to determine the Galactic radial oxygen gradients and other abundance patterns. We select data homogeneously from recent data sets, including PNe at large Galactocentric distances.
L. Stanghellini, M. Haywood
semanticscholar +1 more source
Binary stars as the key to understanding planetary nebulae [PDF]
Nature Astronomy, 2017 Planetary nebulae are traditionally considered to represent the final evolutionary stage of all intermediate-mass stars (∼0.7–8 M☉). Recent evidence seems to contradict this picture.
David Jones, H. Boffin
semanticscholar +1 more source
Planetary Nebulae Shaped by Common Envelope Evolution [PDF]
Galaxies, 2018 The morphologies of planetary nebula have long been believed to be due to wind shaping processes in which a “fast wind” from the central star impacts a previously ejected envelope. It is assumed that asymmetries existing in the “slow wind” envelope would
A. Frank +5 more
semanticscholar +1 more source
Nebular Spectroscopy: A Guide on H ii Regions and Planetary Nebulae [PDF]
, 2017 We present a tutorial on the determination of the physical conditions and chemical abundances in gaseous nebulae. We also include a brief review of recent results on the study of gaseous nebulae, their relevance for the study of stellar evolution ...
M. Peimbert +2 more
semanticscholar +1 more source
Radio Continuum Spectra of Planetary Nebulae
Galaxies, 2018 Radio continuum emission of planetary nebulae is a rich source of information about their structure and physical parameters. Although radio emission is well studied, planetary nebulae show higher spectral indices than expected for homogeneous sphere.
Marcin Hajduk +6 more
doaj +1 more source
The long-period binary central stars of the planetary nebulae NGC 1514 and LoTr 5 [PDF]
, 2017 The importance of long-period binaries for the formation and evolution of planetary nebulae is still rather poorly understood, which in part is due to the lack of central star systems that are known to comprise such long-period binaries.
David Jones +4 more
semanticscholar +1 more source
X-ray Shaping of Planetary Nebulae
Galaxies, 2018 The stellar winds of the central stars of planetary nebulae play an essential role in the shaping of planetary nebulae. In the interacting stellar winds model, the fast stellar wind injects energy and momentum, which are transferred to the nebular ...
Martín A. Guerrero
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Planetary Nebulae as Sources of Chemical Enrichment of the Galaxy
Frontiers in Astronomy and Space Sciences, 2022 During the late asymptotic giant branch (AGB) phase of stellar evolution, the element carbon is created through the triple-α nuclear reaction. This is followed by the synthesis of other heavy elements via neutron capture in the core and the dredge-up of ...
Sun Kwok, Sun Kwok
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Distinguishing between symbiotic stars and planetary nebulae [PDF]
, 2017 Number of known symbiotic stars (SySt) is still significantly lower than their predicted population. One of the main problems in finding complete population of SySt is the fact that their spectrum can be confused with other objects, such as planetary ...
K. Iłkiewicz, J. Mikołajewska
semanticscholar +1 more source
Galaxies, 2018 The increase in discovered close binary central stars of planetary nebulae is leading to a sufficiently large sample to begin to make broader conclusions about the effect of close binary stars on common envelope evolution and planetary nebula formation ...
Todd Hillwig
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