Results 101 to 110 of about 501,439 (210)
Unresolved velocity structure in diffuse interstellar clouds
The Astrophysical Journal, 1988 Recent high-resolution observations of interstellar absorption lines of CH and CN toward Zeta Oph obtained by Crane et al. (1986), and Palazzi et al. (1988), exhibit line widths that suggest thermal line broadening at high temperature, T about 1200 K.
Black, J.H., Dishoeck, E.F. van
openaire +3 more sources
Anomalous Extinction and Diffuse Interstellar Bands In the Direction of 2 Be Stars
, 1992 The Be stars HD 44458 and HD 63462, characterized by peculiar extinction curves, were observed spectroscopically in the range of well-known diffuse interstellar bands - DIBs - (5780, 5797, 6196 and 6203 angstrom). The lack of some of the diffuse features
J. KRELOWSKI +2 more
core
Interstellar shocks and molecular CH/+/ in diffuse clouds
The Astrophysical Journal, 1980 The influence of shocks on the abundances of molecules in diffuse interstellar clouds is investigated with special emphasis on molecular CH/sup +/. Idealized shocks with plausible parameters are found to produce column densities for CH/sup +/ in the hot, postshock gas which are comparable with measured values in interstellar clouds (up to about 10/sup ...
M. Elitzur, W. D. Watson
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88th Annual Meeting of the Meteoritical Society 2026: Abstracts
Meteoritics &Planetary Science, Volume 61, Issue S1, Page S48-S551, August 2026.
wiley +1 more source
Radiative transfer and chemistry in spheroidal interstellar clouds
, 2002 The thesis begins by describing the way in which gas phase chemistry of the interstellar medium can be modelled, and demonstrating the potential significance of chemical reactions on the surfaces of dust grains present in the gas. The dust also serves as
O'Neill, Philip Thomas
core
Mapping the Cosmic-Ray Ionization Rate in the Local Galaxy with
The Astrophysical JournalChemistry in diffuse molecular clouds relies primarily on rapid ion-molecule reactions. Formation of the initial ions, H ^+ and H ${}_{2}^{+}$ , is dominated by cosmic-ray ionization of H and H _2 , making the cosmic-ray ionization rate (denoted ζ (X ...
Nick Indriolo +8 more
doaj +1 more source
On the relation between the carriers of diffuse interstellar bands and simple molecular species [PDF]
, 1997 The interstellar clouds composed mostly of neutral hydrogen (H I clouds) show evident differences in the pattern of interstellar absorptions: in the shapes of the extinction curves, the strengths of the diffuse interstellar bands and the intensities of ...
Galazutdinov G. +3 more
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Molecular Hydrogen Formation via Vibrational Excitation of Partially Superhydrogenated Pyrenes
The Astrophysical JournalWhile polycyclic aromatic hydrocarbons (PAHs) are now accepted to be abundant in interstellar space, the abundance and influence of superhydrogenated PAHs (HPAHs) in the interstellar medium (ISM) are still under investigation.
Frederik Doktor S. Simonsen +6 more
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UniverseGalactic cosmic rays (GCRs), composed of protons and atomic nuclei, are accelerated in sources such as supernova remnants and pulsar wind nebulae, reaching energies up to the PeV range.
Luan Torres, Luiz Augusto Stuani Pereira
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The Astrophysical JournalMolecular hydrogen (H _2 ) formation and dissociation are key processes that drive the gas life cycle in galaxies. Using the SImulating the LifeCycle of Molecular Clouds zoom-in simulation suite, we explore the utility of future observations of H _2 ...
Blakesley Burkhart +13 more
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