Interstellar radiation field and dust temperatures in the diffuse interstellar matter and in giant molecular clouds
J. S. Mathis, P. G. Mezger, N. Panagia;
AaA, 1983, 128, 212
ABSTRACT:The interstellar radiation field (ISRF) is reevaluated as a function of galactocentric distance, in view of the results of recent surveys of
the 2.4 and 3.4 micron galactic emissions, far-IR surveys of the galactic
plane, and an improved model of dust opacity variation in the galactic
plane.
A determination of the radiation field inside Giant Molecular Clouds
(GMCs) as a function of both galactocentric distance and extinction, and a
calculation of the dust temperatures of the Mathis-Rumpl-Nordsiek (1977)
composite graphite/silicate dust model are undertaken.
It is found that the
ISRF, between 0.09 and 8 microns, is dominated by stellar radiation, and by
reemitted radiation from dust grains between 8 and 1000 microns.
The dominant
sources of heating in GMCs are stellar radiation for graphite grains and far-IR
heating for silicate grains.
The stellar radiation absorbed in the outer
layers of GMCs is almost entirely converted into far-IR radiation.
KEYWORDS: cosmic dust, interstellar matter, interstellar radiation, molecular clouds, graphite, radiation distribution, radiative transfer, silicates, temperature profiles
CODE: mathis83