Results 41 to 50 of about 163 (129)
The Astronomical JournalWe report our discovery of a faint nebula surrounding a previously little-studied 15th mag variable star, ASASSN-19ds, in the Southern Hemisphere constellation Antlia. Spectra verify that the star is a cataclysmic variable (CV).
Howard E. Bond +4 more
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The Formation of Binary and Single Nuclei of Planetary Nebulae
The Astrophysical Journal, 1993 We model the evolution of binary systems and explore the possibilities of formation of single and binary planetary nebula nuclei (PNNs). Under the assumption that all stars are born in binary systems, we obtain a Galactic rate of PNN formation of 0.87 yr -1 .
L. R. Yungelson, A. V. Tutukov, M. Livio
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The Formation of Single and Binary Nuclei of Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1993 The present birthrate of binaries may be written as where M1 is the mass of the primary in M⊙, 0 < q ≤ 1 — mass ratio of components, A — semimajor axis of the orbit in R⊙. The Eq.(1) implies that all stars are born as binaries with 10 ≤ A/R⊙ ≤ 106, and that one binary with M1 ≥ 0.8M⊙ is formed annually in the Galaxy.
L. R. Yungelson, A. V. Tutukov
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Spectroscopic Survey of Faint Planetary-nebula Nuclei. V. The EGB 6-type Central Star of Abell 57
The Astrophysical JournalDuring our spectroscopic survey of central stars of faint planetary nebulae (PNe), we found that the nucleus of Abell 57 exhibits strong nebular emission lines.
Howard E. Bond +5 more
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The Critical Role of Dust on the [O iii] Planetary Nebula Luminosity Function’s Bright-end Cutoff
The Astrophysical JournalWe examine the relationship between circumnebular extinction and core mass for sets of [O iii ]-bright planetary nebulae (PNe) in the Large Magellanic Cloud and M31. We confirm that for PNe within 1 magnitude of the planetary nebula luminosity function’s
George H. Jacoby, Robin Ciardullo
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The Astrophysical Journal Supplement SeriesQuenching of star formation plays a fundamental role in galaxy evolution. This process occurs due to the removal of the cold interstellar medium (ISM) or stabilization against collapse, so that gas cannot be used in the formation of new stars.
Oleh Ryzhov +8 more
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A Method of Determination of the Temperature of Nuclei of the Planetary Nebulae [PDF]
Symposium - International Astronomical Union, 1968 I would like to make a few comments on the problem of the determination of the temperatures of nuclei of planetary nebulae.It can be shown that in a high-excitation planetary nebula two independent Strömgren zones of heavy elements can be found. The first is a He III zone; the second corresponds to a zone of the luminescence of Ne V forbidden lines and
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Kepler Discovery of GW Vir Pulsations of the Central Star of Planetary Nebula Kn 61
The Astrophysical JournalWe report the discovery of pulsations in the N-rich PG 1159-type central star of the planetary nebula Kn 61 based on 1 month of Kepler Short Cadence observations. We detect four significant peaks in the frequency range consistent with g -modes excited in
Paulina Sowicka +3 more
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The Temperatures of the Nuclei of Planetary Nebulae [PDF]
Monthly Notices of the Royal Astronomical Society, 1933 R. H. Stoy, A. Eddington
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A Search for Cool Companions of Planetary Nebula Nuclei [PDF]
Symposium - International Astronomical Union, 1989 At present only a small number of planetary nebulae are known to possess binary nuclei. Since approximately 2/3 of main sequence stars are members of binary or multiple star systems, one might expect a large fraction of PN central stars to have gravitationally bound companions.
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