Very small grains and the infrared colors of galaxies

Journal Article · Thu Aug 01 04:00:00 EDT 1991 · Astrophysical Journal; (United States)

DOI:https://doi.org/10.1086/170299· OSTI ID:5257814

Helou, G; Ryter, C; Soifer, B T ^[1]

---

1. JPL, Pasadena, CA (United States) CEA, Centre d'Etudes Nucleaires de Saclay, Gif-sur-Yvette (France) California Institute of Technology, Pasadena (United States)

The contribution of very small grains with fluctuating temperature to the IR emission of disk galaxies is evaluated in light of IRAS data, and the abundance variation of these small grains among galaxies, relative to the 'classical', thermally stable grains, is estimated. It is suggested that the low dispersion in the 'cold' galaxies is representative of the true dispersion in the small-to-large grain abundance ratio among galaxies, while the larger dispersion among warmer galaxies results from increasing optical depth-heating dust effects due to AGNs, in conjunction with the destruction of small dust grains at high radiative energy densities. 53 refs.

• OSTI ID: 5257814
• Journal Information: Astrophysical Journal; (United States), Journal Name: Astrophysical Journal; (United States) Vol. 376; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COLOR
ELECTROMAGNETIC RADIATION
GALAXIES
HEATING
INFRARED RADIATION
INTERSTELLAR GRAINS
INTERSTELLAR SPACE
OPTICAL PROPERTIES
ORGANOLEPTIC PROPERTIES
PARTICLES
PHOTOMETRY
PHYSICAL PROPERTIES
RADIATIONS
SPACE