Results 31 to 40 of about 281,420 (175)

Dust in protoplanetary disks: observations*

EPJ Web of Conferences, 2015
Solid particles, usually referred to as dust, are a crucial component of interstellar matter and of planet forming disks surrounding young stars. Despite the relatively small mass fraction of ≈1% (in the solar neighborhood of our galaxy; this number may ...
Waters L.B.F.M.
doaj   +1 more source

INDUCING INTRINSIC γ-RAY EMISSION OF THE INTERSTELLAR MEDIUM BY INTENSE FLUXES OF PROTONS AND α-PARTICLES IN ACTIVE GALACTIC NUCLEI

Odessa Astronomical Publications, 2020
Cosmic-ray induced γ-ray emission in active galactic nuclei (AGN) has been examined in this study for the first time. Cross-sections for the formation of γ-quanta in such cosmic-ray collisions were selected in the 1-150 MeV energy range.
D. N. Doikov
doaj   +1 more source

Molecule-specific diffusion and desorption of interstellar ices on carbonaceous dust

Astronomy & Astrophysics
Interstellar ices form on dust grains in the coldest regions of molecular clouds and preserve key volatile reservoirs that could be incorporated into protoplanetary disks during star and planet formation.
Chiu Yi-Hsuan, Suhasaria Tushar, Jäger Cornelia, Lee Chun-Yi, Chuang Ko-Ju, Henning Thomas, Chen Yu-Jung   +6 more
doaj   +1 more source

Modelling DESTINY+ interplanetary and interstellar dust measurements en route to the active asteroid (3200) Phaethon [PDF]

, 2019
The JAXA/ISAS spacecraft DESTINY+ will be launched to the active asteroid (3200) Phaethon in 2022. Among the proposed core payload is the DESTINY+ Dust Analyzer (DDA) which is an upgrade of the Cosmic Dust Analyzer flown on the Cassini spacecraft to ...
Agarwal, J., Kobayashi, Masanori, Krüger, H., Sommer, Maximilian, Agarwal, Jessica, Kobayashi, M., Kimura, H., Arai, T., Altobelli, N., Grün, Eberhard, Sterken, Veerle J., Sterken, V., Grün, E., Kimura, Hiroshi, Moragas-Klostermeyer, G., Krueger, H., Krüger, Harald, Hirai, T., Sommer, M., Strub, P., Srama, Ralf, Moragas-Klostermeyer, Georg, Altobelli, Nicolas, Strub, Peter, Arai, Tomoko, Srama, R., Hirai, Takayuki   +26 more
core   +2 more sources

Interstellar X-Ray Absorption and Scattering

The Astrophysical Journal
Accurate estimates of the absorption of X-rays by interstellar gas and dust are of crucial importance for the analysis and interpretation of almost all astronomical soft X-ray observations.
Linli Yan, Aigen Li, Fangjun Lu
doaj   +1 more source

The nature of interstellar dust as revealed by light scattering

Atti della Accademia Peloritana dei Pericolanti : Classe di Scienze Fisiche, Matematiche e Naturali, 2011
Interstellar dust was first identified through the extinction that it causes of optical starlight. Initially, observational and theoretical studies of extinction were made to identify simple ways of removing the effect of extinction.
D. A. Williams
doaj   +1 more source

One Relation for All Wavelengths: The Far-ultraviolet to Mid-infrared Milky Way Spectroscopic R(V)-dependent Dust Extinction Relationship

The Astrophysical Journal, 2023
Dust extinction is one of the fundamental measurements of dust grain sizes, compositions, and shapes. Most of the wavelength-dependent variations seen in Milky Way extinction are strongly correlated with the single parameter R ( V ) = A ( V )/ E ( B − V )
Karl D. Gordon, Geoffrey C. Clayton, Marjorie Decleir, E. L. Fitzpatrick, Derck Massa, Karl A. Misselt, Erik J. Tollerud   +6 more
doaj   +1 more source

VUV and mid‐UV photoabsorption cross sections of thin films of glycine and alanine: Application to their photochemistry in the solar system

Photochemistry and Photobiology, EarlyView.
Thin solid films of pure glycine or alanine (thicknesses ranging from 10 to 700 nm) were prepared on MgF2 windows using a vacuum sublimation/recondensation method. VUV‐UV spectroscopy of these films enabled us to characterize new absorption cross sections for glycine and alanine for VUV‐UV radiations between 120 and 300 nm.
Juliette Pastore, Hervé Cottin, Kafila Saïagh, Jodie Belilla, Fabien Stalport, Nicolas Fray, Nathalie Carrasco   +6 more
wiley   +1 more source

The formation of molecular hydrogen in the interstellar medium [PDF]

, 2010
H2 is the most abundant molecule in the interstellar medium and forms on the surface of interstellar dust grains. Laboratory studies have been conducted of HD formation on a dust grain analogue, which is a highly-oriented pyrolytic graphite surface ...
Islam, F.
core  

On Our Cosmic (In)significance

Ratio, EarlyView.
ABSTRACT This article discusses three interpretations of cosmic significance, all of which reveal something important about the notion of significance. Along the way, it proposes a unified view of significance by combining elements of each of the views.
Oskari Sivula
wiley   +1 more source