Results 81 to 90 of about 1,537 (221)
Small scale structure in circumstellar envelopes and the origin of globules in planetary nebulae
, 2002 We analyze the small scale structure in the circumstellar envelopes of NGC 7027 and IRC+10216, using high resolution optical images in dust scattered light.
P. J. Huggins, N. Mauron
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The Astronomical JournalThe carrier of the 21 μ m emission feature discovered in a handful of protoplanetary nebulae (PPNe) is one of the most intriguing enigmas in circumstellar chemistry.
Jian-Jie Qiu +9 more
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The excitation of circumstellar C
, 2013 Context. Observations of the circumstellar envelopes of post-asymptotic giant branch (post-AGB) stars provide information about their mass-loss history during the AGB phase and about the chemistry inside envelopes after that phase. Aims.
M. Pułecka +3 more
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The unique chemistry in the envelopes of massive stars
Frontiers in Astronomy and Space SciencesThe envelopes of evolved massive stars (M ∼9–40 M⊙) on the Red Supergiant (RSG) Branch offer a unique situation to examine extreme circumstellar chemistry.
Lucy M. Ziurys
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The abundance of SiS in circumstellar envelopes around AGB stars
, 2007 Aims.Given their photospheric origin and refractive nature, SiS molecules can provide major constraints on the relative roles of dust condensation and non-equilibrium processes in regulating the chemistry in circumstellar envelopes around evolved stars.
H. Olofsson +8 more
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The Astrophysical JournalRecent high-resolution observations have enabled detailed investigations of the circumstellar environments around Class 0/I protostars. Several studies have reported that the infall velocity of the envelope is a few times smaller than the freefall ...
Shingo Hirano +2 more
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Multiple Protostellar Outflows from a Single Protostar with a Misaligned Disk
The Astrophysical JournalWe investigate how misalignment between the core angular momentum and the large-scale magnetic field affects protostellar outflows, and whether a single protostellar system can drive multiple outflow components.
Shingo Hirano +2 more
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Journal of Saudi Chemical Society, 2016 The ring expansion reaction mechanisms between cyclopropenylidene and cyclic CnH2nO (n = 2, 3) compounds have been systematically investigated employing the second-order Møller-Plesset perturbation theory (MP2) method in order to better understand the ...
Xiaojun Tan, Weihua Wang, Ping Li
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Molecules, Dust and the Structure of Circumstellar Envelopes
, 2007 . Radio continuum and spectral line emission from the photospheres and circumstellar shells of evolved cool giant stars trace their size, shape and mass loss history.
G. R. Knapp
core
Open Astronomy, 2017 Ongoing studies of different groups of stars result in improving our knowledge of their fundamental parameters and evolutionary status. Also, they result in finding new phases of stellar evolution, which require theoretical explanation. At the same time,
Miroshnichenko Anatoly S. +9 more
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