Open AccessPorous interstellar grains
Author(s) -
Iatì M. A.,
CecchiPestellini C.,
Williams D. A.,
Borghese F.,
Denti P.,
Saija R.,
Aiello S.
Publication year - 2001
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2001.04166.x
Subject(s) - physics , cosmic dust , interstellar medium , extinction (optical mineralogy) , multipole expansion , stars , astrophysics , scattering , porosity , porous medium , cosmochemistry , interstellar cloud , astronomy , galaxy , optics , composite material , materials science , quantum mechanics
Recent observations of stellar composition suggest that elements in the Sun are significantly more abundant than in other stars. The reduction in the available element budget implies a drastic revision in current models of interstellar dust. Theoretical models are therefore exploring fluffy, porous physical structure for the grain material. Since a detailed exact treatment of extinction cross‐sections is mandatory for a correct understanding of the nature of interstellar dust, we present a technique based on the multipole expansions of the electromagnetic field, which has proven to be general, flexible and powerful in treating scattering of light by porous, composite, arbitrarily shaped particles. The results of this study speak in favour of core–mantle structures characterized by the presence of porosities.