Open AccessInelastic dissipation in a freely rotating body: application to cosmic dust alignment
Author(s) -
Lazarian A.,
Efroimsky Michael
Publication year - 1999
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.1365-8711.1999.02235.x
Subject(s) - physics , dissipation , relaxation (psychology) , oblate spheroid , inelastic collision , condensed matter physics , classical mechanics , nuclear physics , thermodynamics , psychology , social psychology , electron
Motivated by a recent study by Lazarian and Draine, which showed that a high degree of grain alignment of the paramagnetic dust is achievable if the rates of internal relaxation are controlled by the Barnett relaxation process, we undertake a study of an alternative mechanism of internal dissipation, namely, the inelastic dissipation of energy in oblate dust grains. We find that deformations at double frequency that were disregarded in earlier studies dominate the inelastic relaxation. Our results indicate that for sufficiently oblate grains, e.g. for grains with a 4:1 axis ratio, or/and grains formed by agglomeration, inelastic relaxation dominates the Barnett relaxation within large (a > 0.1 μm) grains. For grains with an axis ratio less than 1:2, the inelastic relaxation is dominant for suprathermally rotating grains.