Results 31 to 40 of about 163 (129)
Spectroscopic Survey of Faint Planetary-nebula Nuclei. IV. The A35-type Central Star of Pa 27
The Astrophysical JournalWe present optical spectroscopy of the 12th-magnitude central star of the planetary nebula (PN) Patchick 27 (Pa 27), obtained during a survey of faint PN nuclei (PNNs) with the Low-Resolution Spectrograph of the Hobby–Eberly Telescope.
Howard E. Bond, Gregory R. Zeimann
doaj +1 more source
UBV Photometry of the Bright Nuclei of the Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1968 The data, which we have at present for the planetary nebulae central stars, are in general insufficient and uncertain. Even the photographic magnitudes of the brightest nuclei are usually given in the known catalogues with accuracies of 2m or 3m. Therefore, the determination of central stars' magnitudes by the photoelectric method seems to be of great ...
E. B. Kostjakova +3 more
openaire +1 more source
The Astrophysical JournalA consensus has been reached in recent years that binarity plays an important role in the formation and evolution of a significant fraction of planetary nebulae (PNe).
Pinjian Chen +3 more
doaj +1 more source
The Astronomical JournalPlanetary nebulae (PNe) shown to be members of star clusters provide information on their properties and evolutionary histories that cannot be determined for PNe in the field, in particular the initial masses of their progenitor stars.
Andrea Bellini +2 more
doaj +1 more source
The Astronomical JournalIf a planetary nebula (PN) is shown to be a member of a star cluster, we obtain important new constraints on the mass and chemical composition of the PN’s progenitor star, which cannot be determined for PNe in the field.
Howard E. Bond +2 more
doaj +1 more source
KINEMATICAL PROPERTIES OF PLANETARY NEBULAE WITH WR-TYPE NUCLEI
Publications of The Korean Astronomical Society, 2015 We have carried out integral field unit (IFU) spectroscopy of H$α$, [N II] and [O III] emission lines for a sample of Galactic planetary nebulae (PNe) with Wolf-Rayet (WR) stars and weak emission-line stars (wels). Comparing their spatially-resolved kinematic observations with morpho-kinematic models allowed us to disentangle their three-dimensional ...
Parker, QA, Steffen, W, Danehkar, A
openaire +4 more sources
The Possibility of Beta decay in the Atmospheres of Nuclei of Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1968 At present there is some basis for questioning the usual presentation of the nuclei of planetary nebulae as being ordinary stars. If the quantity of mass released by a star during its formation or at some stage of its evolution serves as a criterion for its not being stationary, then the nuclei of planetary nebulae are hardly the most non-stationary ...
openaire +1 more source
The Astrophysical JournalPlanetary nebulae (PNs) that are physically associated with star clusters are rare but crucial for stellar-evolution studies because they allow their initial and final stellar properties to be determined independently, contributing to constraints on the ...
Vasiliki Fragkou +4 more
doaj +1 more source
Morphologies of Planetary Nebulae with Close-Binary Nuclei [PDF]
Symposium - International Astronomical Union, 1989 We will present photographic and CCD images of planetary nebulae that are known, on the basis of photometric observations of the central stars, to possess close-binary nuclei. All of the orbital periods range from 2.7 to 16 hours, except for the 16-day binary nucleus of NGC 2346.
Howard E. Bond +2 more
openaire +1 more source
Protoplanetary Nebulae Are Not the Precursors of Planetary Nebulae with Close Binary Central Stars
The Astronomical JournalProtoplanetary nebulae are considered to be the evolutionary link between asymptotic giant branch stars and planetary nebulae. They possess many of the physical characteristics expected of such a link and provide valuable information about the ...
Todd C. Hillwig +2 more
doaj +1 more source