Results 11 to 20 of about 219,513 (216)

Measuring the fractal structure of interstellar clouds [PDF]

open access: yesSymposium - International Astronomical Union, 1991
To study the structure of interstellar clouds we used the so-called perimeter-area relation to estimate fractal dimensions. We studied the reliability of the method by applying it to artificial fractals and discuss some of the problems and pitfalls. Results for two different cloud types (high-
Vogelaar, M.G.R   +2 more
openaire   +3 more sources

Photodissociation of OH in Interstellar Clouds

open access: yesThe Astrophysical Journal, 1984
Calculations are presented of the lifetime of OH against photodissociation by the interstellar radiation field as a function of depth into interstellar clouds containing grains of various scattering properties. The effectiveness of the different photodissociation channels changes with depth into a cloud. Absorption into the repulsive - state is usually
Dishoeck, E.F. van, Dalgarno, A.
openaire   +4 more sources

The Origin of the Cluster of Local Interstellar Clouds

open access: yesThe Astrophysical Journal
The interstellar medium within ≈15 pc of the Sun consists of a complex of 15 diffuse, partially ionized clouds. Located within the Local Bubble, these clouds, known as the Cluster of Local Interstellar Clouds (CLIC), constitute the interstellar ...
Catherine Zucker   +4 more
doaj   +2 more sources

Hierarchical structure of the interstellar molecular clouds and star formation [PDF]

open access: yesOpen Astronomy, 2017
Properties of the hierarchical structures of interstellar molecular clouds are discussed. Particular attention is paid to the statistical correlations between velocity dispersion and size, and between the magnetic field strength and gas density.
Dudorov Alexander E.   +1 more
doaj   +2 more sources

CaFe interstellar clouds* [PDF]

open access: yesMonthly Notices of the Royal Astronomical Society, 2007
A new kind of interstellar cloud is proposed. These are rare (just a few examples among ∼300 lines of sight) objects with the Ca I 4227-Å, Fe I 3720-Å and 3860-Å lines stronger than those of K I (near 7699 Å) and Na I (near 3302 Å). We propose the name ‘CaFe’ for these clouds.
A. Bondar   +5 more
openaire   +2 more sources

The Rich Chemistry of Ionized Methanol With Sulfur Dioxide: Pathways to Prebiotic and Elusive Species in Earth's Atmosphere and Space. [PDF]

open access: yesChemistry
The reaction between the methanol radical cation and sulfur dioxide is remarkably fast and forms several ionic and neutral products (HOSOH+, CH2OSO+, CH2OH+, CH2O, H2O, HSO2). The chemistry goes beyond simple proton or hydrogen transfer, revealing a close interaction between the two species, relevant to atmospheric and astrochemical environments where ...
Satta M   +3 more
europepmc   +2 more sources

Submillimetre molecular line observations and modelling of molecular clouds. [PDF]

open access: yes, 1985
PhDSubmillimetre molecular line observations of molecular clouds in our galaxy are presented, and the data analysed using various alternative cloud models.
Richardson, Kevin John
core   +4 more sources

Mixing Interstellar Clouds Surrounding the Sun [PDF]

open access: yes, 2022
On its journey through the Galaxy, the Sun passes through diverse regions of the interstellar medium. High-resolution spectroscopic measurements of interstellar absorption lines in spectra of nearby stars show absorption components from more than a ...
Linsky, Jeffrey L   +17 more
core   +1 more source

Inhomogeneity within Local Interstellar Clouds [PDF]

open access: yes, 2022
Analysis of interstellar absorption lines observed in high-resolution {\em HST} spectra of nearby stars provides temperatures, turbulent velocities, and kinetic properties of warm interstellar clouds. Previous studies identified 15 warm partially ionized
Chasan-Taber, Adina   +4 more
core   +1 more source

The mass spectrum of interstellar clouds [PDF]

open access: yesInternational Astronomical Union Colloquium, 1989
AbstractThe abundance of 21-cm absorption lines seen in surveys at high latitudes can be translated into a line of sight abundance of clouds vs. column density using an empirical relationship between temperature and optical depth. As VLA surveys of 21-cm absorption at low latitudes are now becoming available, it is possible to study the variation of ...
John M. Dickey, Robert W. Garwood
openaire   +1 more source

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