Results 1 to 10 of about 647 (136)
n-Alkanes formed by methyl-methylene addition as a source of meteoritic aliphatics [PDF]
Communications ChemistryAliphatics prevail in asteroids, comets, meteorites and other bodies in our solar system. They are also found in the interstellar and circumstellar media both in gas-phase and in dust grains.
P. Merino +16 more
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Is Phenylnitrene a Missing Link in the Formation of Polycyclic Aromatic Nitrogen Heterocycles? [PDF]
Angew Chem Int Ed EnglA new formation pathway for polycyclic aromatic nitrogen heterocycles (PANHs) has been found. The reaction of phenylnitrene and the propargyl radical leads to quinoline, proving that nitrenes are suitable precursors for nitrogen incorporation mechanisms.
Arns R +6 more
europepmc +2 more sources
Origin of compact exoplanetary systems during disk infall [PDF]
Nature CommunicationsExoplanetary systems that contain multiple planets on short-period orbits appear to be prevalent in the current observed exoplanetary population, yet the processes that give rise to such configurations remain poorly understood.
Raluca Rufu, Robin M. Canup
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AGB Stars and Their Circumstellar Envelopes. I. the VULCAN Code
Universe, 2021 The interplay between AGB interiors and their outermost layers, where molecules and dust form, is a problem of high complexity. As a consequence, physical processes like mass loss, which depend on the chemistry of the circumstellar envelope, are often ...
Sergio Cristallo +4 more
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NIKA2 observations around LBV stars Emission from stars and circumstellar material [PDF]
EPJ Web of Conferences, 2020 Luminous Blue Variable (LBV) stars are evolved massive objects, previous to core-collapse supernova. LBVs are characterized by photometric and spectroscopic variability, produced by strong and dense winds, mass-loss events and very intense UV radiation ...
Ricardo Rizzo J. +2 more
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Takeout and Delivery: Erasing the Dusty Signature of Late-stage Terrestrial Planet Formation
The Astrophysical Journal, 2023 The formation of planets like Earth is expected to conclude with a series of late-stage giant impacts that generate warm dusty debris, the most anticipated visible signpost of terrestrial planet formation in progress.
Joan R. Najita, Scott J. Kenyon
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AC Her: Evidence of the First Polar Circumbinary Planet
The Astrophysical Journal Letters, 2023 We examine the geometry of the post–asymptotic giant branch (AGB) star binary AC Her and its circumbinary disk. We show that the observations describe a binary orbit that is perpendicular to the disk with an angular momentum vector that is within 9° of ...
Rebecca G. Martin +4 more
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MODELS OF CIRCUMSTELLAR MASERS IN BIPOLAR OUTFLOWS
Odessa Astronomical Publications, 2017 Sources of molecular maser radio emission in envelopes of late-type variable stars (red giants and supergiants) are considered. Radio and optical data on asymmetry of mass loss process in red giants are briefly reviewed.
G. M. Rudnitskij
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Odessa Astronomical Publications, 2017 By using the spectra taken at 6m telescope and the methods of two-dimensional spectral classification, the non-ordinarity of the main star in RZ Eri is shown.
V. G. Karetnikov +2 more
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Dust Coagulation in Oxygen-rich Circumstellar Outflows
The Astrophysical Journal, 2023 We show that the inefficient growth of SiO molecules on (SiO) _x dust grains prolongs the period of maximum dust nucleation in circumstellar outflows resulting in a several orders-of-magnitude increase in the dust density near the star.
John A. Paquette +2 more
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