Results 21 to 30 of about 2,128 (220)
Interstellar processes: Ortho/para conversion, radiative association, and dissociative recombination
EPJ Web of Conferences, 2015 The study of the ortho-to-para ratio of assorted gas-phase interstellar molecules such as H2, H2O, NH3, and H2O+ has gained interest in recent years, based partially on new spectral observations of light hydrides by the Herschel Space Observatory ...
Herbst Eric
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The Role of Magnetic Field in Molecular Cloud Formation and Evolution
Frontiers in Astronomy and Space Sciences, 2019 We review the role that magnetic field may have on the formation and evolution of molecular clouds. After a brief presentation and main assumptions leading to ideal MHD equations, their most important correction, namely the ion-neutral drift is described.
Patrick Hennebelle +2 more
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Where Does the Energy Go during the Interstellar NH3 Formation on Water Ice? A Computational Study
The Astrophysical Journal, 2023 In the coldest (10–20 K) regions of the interstellar medium, the icy surfaces of interstellar grains serve as solid-state supports for chemical reactions.
Stefano Ferrero +5 more
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The Formation of Large Hydrocarbons and Carbon Clusters in Dense Interstellar Clouds [PDF]
, 1997 Current gas-phase models of dense cloud chemistry contain molecules through approx 10 atoms in size. We have extended two current reaction networks to include unsaturated hydrocarbons and bare carbon clusters up to 64 carbon atoms in size.
Herbst, Eric, Bettens, R. P. A.
core +1 more source
The Ionization Rate in Dense Interstellar Clouds [PDF]
Symposium - International Astronomical Union, 1987 Measurements of the abundances of OH, HCO+ and DCO+ are employed to derive the ionization rate in molecular clouds.
S. Lepp, A. Dalgarno
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Proton and Electron Irradiations of CH4:H2O Mixed Ices
Atoms, 2023 The organic chemistry occurring in interstellar environments may lead to the production of complex molecules that are relevant to the emergence of life. Therefore, in order to understand the origins of life itself, it is necessary to probe the chemistry ...
Duncan V. Mifsud +9 more
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Kinematics of H I Envelopes Associated with Molecular Clouds
The Astronomical JournalWe investigate the evolution of molecular clouds through the kinematics of their atomic hydrogen (H I ) envelopes, using ^12 CO and 21 cm emission to trace the molecular and atomic gas, respectively.
Thummim Mekuria, Nia Imara
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Deuterium fractionation in dense interstellar clouds
The Astrophysical Journal, 1989 The time-dependent gas-phase chemistry of deuterium fractionation in dense interstellar clouds ranging in temperature between 10 and 70 K was investigated using a pseudo-time-dependent model similar to that of Brown and Rice (1986). The present approach, however, considers much more complex species, uses more deuterium fractionation reactions, and ...
Millar, TJ, Bennett, A., Herbst, E.
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Meteoritics &Planetary Science, EarlyView.Abstract Amorphous carbon (αC) is found in various extraterrestrial particles, including those thought to originate from the outer Solar System. αC can form through two main processes involving C‐rich materials: exposure to energetic charged particles and thermal processing.
M. Germanà +10 more
wiley +1 more source
A High-mass, Young Star-forming Core Escaping from Its Parental Filament
The Astrophysical Journal, 2023 We studied the unique kinematic properties in massive filament G352.63-1.07 at 10 ^3 au spatial scale with the dense molecular tracers observed with the Atacama Large Millimeter/submillimeter Array.
Zhiyuan Ren +19 more
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