Analysis of the interstellar material in the line of sight toward Omicron Persei

Journal Article · Mon Mar 15 04:00:00 EST 1976 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/154223· OSTI ID:7365088

Snow, Jr, T P

Ultraviolet spectrophotometric data obtained with the satellite Copernicus are used to analyze the chemical abundances and physical conditions in the line of sight toward o Per(B1 III,E (B-V) =0.32). Data obtained at high resolution (0.05 A) are presented for 69 lines due to ions and atoms and 19 lines of H/sub 2/ and HD. In addition, lower-resolution (0.2 A) scans are used to derive the column densities of Hi and H/sub 2/ as well as the far-ultraviolet extinction curve. The star may be embedded in the near edge of a dense molecular cloud, the outer portions of which give rise to the observed absorption lines. The far-ultraviolet extinction rise is unusually steep, indicating the probably presence of a high proportion of very small grains. The overall fraction of hydrogen nuclei in H/sub 2/ molecules is 0.52, and may be significantly higher in the region containing most of the molecules. The gas-to-dust ratio N/sub H//E (B-V) =4.41-5.38 x 10/sup 21/ cm/sup -2/ mag/sup -1/ is normal, although the overall space density of hydrogen nuclei n/sub H/ =1.42-1.73 cm/sup -3/ is somewhat higher than the typical value. The depletions of elements are generally somewhat greater than in other clouds analyzed with Copernicus. The density in the region containing the observed C i lines is probably a few hundred cm/sup -3/, and may be in excess of 1000 cm/sup -3/ in the portion of the cloud where the observed molecules exist. Only a small fraction of the total mass in the line of sight is contained in the H ii region. (AIP)

• Research Organization: Princeton University Observatory
• OSTI ID: 7365088
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 204:3; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION SPECTRA
ALKALINE EARTH METALS
ARGON
CARBON
CHEMICAL COMPOSITION
CHEMISTRY
CHLORINE
COPPER
COSMIC DUST
COSMIC GASES
COSMIC RADIO SOURCES
COSMOCHEMISTRY
CRYOGENIC FLUIDS
DENSITY
DUSTS
ELEMENTS
FLUIDS
GASES
H2 REGIONS
HALOGENS
HYDROGEN
INTERSTELLAR GRAINS
INTERSTELLAR SPACE
IRON
MAGNESIUM
MANGANESE
METALS
MOLECULES
NICKEL
NITROGEN
NONMETALS
OXYGEN
PARTICLES
PHOSPHORUS
PHYSICAL PROPERTIES
RARE GASES
SEMIMETALS
SILICON
SPACE
SPECTRA
SPECTROPHOTOMETRY
SULFUR
TITANIUM
TRANSITION ELEMENTS
ULTRAVIOLET SPECTRA