Destruction mechanisms for interstellar dust

Journal Article · Sun Jul 15 04:00:00 EDT 1979 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/157206· OSTI ID:5828618

Draine, B T; Salpeter, E E

Destruction rates are estimated for interstellar dust grains as a function of size and composition of the grains, and the type of region in which the grain is located. Several idealized models of the interstellar medium are considered. The destruction mechanisms examined include sputtering and grain-grain collisions in interstellar shocks, sputtering and sublimation in H II regions, photodesorption by UV, sputtering by cosmic rays, and sublimation during a supernova radiation pulse. Sublimation by the supernova radiation pulse is found to be very important for the more volatile mantle materials (binding energy U/sub o/ < or = 0.2 eV per molecule). For less volatile molecular ices (e.g., H/sub 2/O with U/sub o/ approx. = 0.5 eV), photodesorption rates are uncertain by several orders of magnitude, however. Sputtering in high-velocity (upsilon/sub s/> or =150 km s/sup -1/) shocks and grain-grain collisions in low-velocity (upsilon/sub s/< or =50 km s/sup -1/) shocks account for most refractory grain destruction. Polymerized ''HCO-material'' is almost as resistant to sputtering as refractory grains. Water icemantles may be marginally able to survive in low-density H II regions (n/sub H/< or approx. =10 cm/sup -3/), especially if the gas temperature is T< or approx. =10/sup 3.8/ K. The implications of these destruction rates for the survival of interstellar grains are briefly discussed.

• Research Organization: Harvard-Smithsonian Center for Astrophysics
• OSTI ID: 5828618
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 231:2; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics &amp; Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CHEMICAL COMPOSITION
COLLISIONS
COSMIC DUST
COSMIC RADIATION
COSMIC RADIO SOURCES
DUSTS
ERUPTIVE VARIABLE STARS
EVAPORATION
H2 REGIONS
INTERSTELLAR GRAINS
IONIZING RADIATIONS
MOLECULE COLLISIONS
MOLECULE-MOLECULE COLLISIONS
PARTICLES
PHASE TRANSFORMATIONS
RADIATIONS
SHOCK WAVES
SPUTTERING
STARS
SUBLIMATION
SUPERNOVAE
VARIABLE STARS