Evolution of grain size distribution with enhanced abundance of small carbonaceous grains in galactic environments [PDF]
Monthly Notices of the Royal Astronomical Society, 2022 We propose an updated dust evolution model that focuses on the grain size distribution in a galaxy. We treat the galaxy as a one-zone object and include five main processes (stellar dust production, dust destruction in supernova shocks, grain growth by
H. Hirashita
semanticscholar +4 more sources
Oxygen isotopic composition of relict olivine grains in cosmic spherules: Links to chondrules from carbonaceous chondrites [PDF]
Geochimica Et Cosmochimica Acta, 2015 Most olivine relict grains in cosmic spherules selected for the present study are pristine and have not been disturbed during their atmospheric entry, thereby preserving their chemical, mineralogical and isotopic compositions.
N G Rudraswami, M Shyam Prasad
exaly +5 more sources
Enhanced star formation through the high-temperature formation of H2 on carbonaceous dust grains [PDF]
Nature Astronomy, 2023 The microphysics of molecular hydrogen formation has an influence on galactic-scale star-formation rates over cosmic time. H_2 is the cooling agent needed to initiate the cloud collapse regulating the star-formation efficiency.
Francesco Grieco +3 more
semanticscholar +3 more sources
Identification of Silicate and Carbonaceous Presolar Grains in the type 3 Enstatite Chondrites [PDF]
AIP Conference Proceedings, 2008 We surveyed presolar grains in primitive enstatite chondrites by isotopography using the HokuDai isotope microscope system. The mineral identification has been conducted by X‐ray analysis with scanning electron microscopy. The chemical compositions are determined for eight silicate and ten carbonaceous presolar grains.
Shingo Ebata +8 more
core +5 more sources
THE 6 μm FEATURE AS A TRACER OF ALIPHATIC COMPONENTS OF INTERSTELLAR CARBONACEOUS GRAINS [PDF]
Astrophysical Journal, 2016 ABSTRACT An unidentified infrared emission (UIE) feature at 6.0 μm is detected in a number of astronomical sources showing the UIE bands. In contrast to the previous suggestion that this band is due to C=O vibrational modes, we suggest that the 6.0 μm feature arises from olefinic double-bond functional groups.
Seyedabdolreza Sadjadi, Sun Kwok
exaly +9 more sources
Energy partitioning in H<sub>2</sub> formation on interstellar carbonaceous grains. Insights from <i>ab initio</i> molecular dynamics simulations. [PDF]
Phys Chem Chem PhysAltres ajuts: acords transformatius de la UABMolecular hydrogen (H) stands as the most abundant molecule within the interstellar medium (ISM), primarily originating from the coupling of two H atoms on the surfaces of dust grains.
Jubert L +3 more
europepmc +4 more sources
Thermal fluctuations and nanoscale effects in the nucleation of carbonaceous dust grains [PDF]
Monthly Notices of the Royal Astronomical Society, 2010 We investigate the role of thermal fluctuations and of the finite number of monomers in small clusters of carbon atoms on the nucleation rate of carbonaceous grains. Thermal fluctuations are due to the quantized nature of the energy exchanges between the
Adam C. Keith, Davide Lazzati
semanticscholar +6 more sources
Structure and evolution of interstellar carbonaceous dust. Insights from the laboratory
Frontiers in Astronomy and Space Sciences, 2022 A large fraction of interstellar carbon is locked up in solid grains. The nature, origin and evolution of these grains have been investigated for decades.
Víctor J. Herrero +5 more
doaj +2 more sources
Luminescence from Small Carbonaceous Dust Grains [PDF]
Symposium - International Astronomical Union, 1990 A relationship exists between the amount of the ultraviolet (UV) extinction and the relative strength of the very broad structure (VBS) in the 500–600 nm wavelength region (5000–6000 Å) of the interstellar extinction curve. It is based on observations of OB stars distributed along the Milky Way.
Christian Friedemann, H. G. Reimann
openalex +2 more sources