Interstellar depletions and the filling factor of the hot interstellar medium

Journal Article · Mon Oct 15 00:00:00 EDT 1979 · Astrophys. J., Lett. Ed.; (United States)

DOI:https://doi.org/10.1086/183081· OSTI ID:5631580

Dwek, E; Scalo, J M

We have examined theoretically the evolution of refractory interstellar grain abundances and corresponding metal deplections in the solar neighborhood. The calculations include a self-consistent treatment of red-giant winds, planetary nebulae, protostellar nebulae, and suprnovae as sources of grains and star formation, and of encounters with supernova blast waves as sinks. We find that in the standard two-phase model for the interstellar medium (ISM), grain destruction is very efficient, and the abundance of refractory grains should be negligible, contrary to observations. In a cloudy three-phase ISM most grains reside in the warm and cold phases of the medium. Supernova blast waves expand predominantly in the hot and tenuous phase of the medium and are showed down as they propagate through a cloud. In order to obtain significant (approx.3) depletions of metals presubably locked up in refractory grain cores, the destruction of grains that reside in the clouds must be minimal. This requires that (a) the density contrast between the cloud and intercloud medium be sufficiently high, and (b) the filling factor of the hot and tenuous gas of the interstellar medium, which presumably gives rise to the O VI absorption and soft X-ray emission, be nearly unity. Much larger depletions (> or approx. =10) must reflect accretion of mantles within interstellar clouds.

• Research Organization: W. K. Kellogg Radiation Laboratory, California Institute of Technology
• OSTI ID: 5631580
• Journal Information: Astrophys. J., Lett. Ed.; (United States), Vol. 233:2
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
INTERSTELLAR GRAINS
ABUNDANCE
CHEMICAL COMPOSITION
COSMIC GASES
INTERSTELLAR SPACE
PLANETARY NEBULAE
RED GIANT STARS
SHOCK WAVES
STAR ACCRETION
STELLAR WINDS
SUPERNOVA REMNANTS
SUPERNOVAE
COSMIC RADIO SOURCES
ERUPTIVE VARIABLE STARS
FLUIDS
GASES
GIANT STARS
NEBULAE
PARTICLES
SPACE
STAR EVOLUTION
STARS
VARIABLE STARS
640105* - Astrophysics & Cosmology- Galaxies