Results 1 to 10 of about 54,405 (244)
Inhomogeneity within Local Interstellar Clouds*
The Astronomical Journal, 2022 Abstract Analysis of interstellar absorption lines observed in high-resolution Hubble Space Telescope spectra of nearby stars provides temperatures, turbulent velocities, and kinetic properties of warm interstellar clouds. A new analysis of 97 interstellar-velocity components reveals a wide range of temperatures and turbulent velocities ...
Jeffrey L. Linsky +3 more
openaire +2 more sources
Learning from model grids: Tracers of the ionization fraction in the ISM [PDF]
EPJ Web of Conferences, 2022 The ionization fraction in neutral interstellar clouds is a key physical parameter controlling multiple physical and chemical processes, and varying by orders of magnitude from the UV irradiated surface of the cloud to its cosmic-ray dominated central ...
Bron Emeric +29 more
doaj +1 more source
FORMATION OF SMALL-SCALE STRUCTURES IN THEINTERSTELLAR MEDIUM
Odessa Astronomical Publications, 2008 We consider formation of small scale structures in the process of interstellar cloud destruction by shock waves. We calculate statistical properties of HI column densities, optical depth and brightness temperature in 21 cm line.
E. E. Matvienko +2 more
doaj +1 more source
Interstellar hydrocarbons: degradation chemistry in diffuse clouds [PDF]
Monthly Notices of the Royal Astronomical Society, 2022 ABSTRACT Observations of diffuse clouds showed that they contain a number of simple hydrocarbons [e.g. CH, C2H, (l- and c-)C3H2, and C4H] in abundances that may be difficult to understand on the basis of conventional gas-phase chemical models.
Zainab Awad, Serena Viti
openaire +4 more sources
Turbulence in Interstellar Clouds [PDF]
International Astronomical Union Colloquium, 1989 Above masses of the order of lOO M⊙, molecular clouds have masses and sizes which scale like those of self-gravitating polytropes bounded by an external pervading pressure. It is unlikely that this scaling is due to mere observational bias. But the physics underlying this behaviour is far from being understood.
openaire +1 more source
The Astrophysical Journal Letters, 2023 Observations of OH ^+ are used to infer the interstellar cosmic ray ionization rate in diffuse atomic clouds, thereby constraining the propagation of cosmic rays through and the shielding by interstellar clouds, as well as the low energy cosmic ray ...
Ábel Kálosi +14 more
doaj +1 more source
The Astrophysical Journal, 2023 The formation of complex organic molecules by simulated secondary electrons generated in the track of galactic cosmic rays was investigated in interstellar ice analogs composed of methanol and carbon dioxide.
Joshua H. Marks +5 more
doaj +1 more source
CLOUD STRUCTURE OF INTERSTELLAR MATTER. OBSERVATIONAL PARAMETERS
Odessa Astronomical Publications, 2017 Parameters of 7600 HI clouds were determined on the base of HI RATAN-600 Survey in the second and third quadrants of galactic longitudes. The spectra of cloud linear diameters, HI densities and masses are obtained first for such huge population of clouds.
I. V. Gosachinskij, V. V. Morozova
doaj +1 more source
Discovery of the Elusive Carbonic Acid (HOCOOH) in Space
The Astrophysical Journal, 2023 A quarter century after the detection of the last interstellar carboxylic acid, acetic acid (CH _3 COOH), we report the discovery of a new one, the cis-trans form of carbonic acid (HOCOOH), toward the Galactic center molecular cloud G+0.693–0.027. HOCOOH
Miguel Sanz-Novo +14 more
doaj +1 more source
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
doaj +1 more source