THE MAGNETIC-ORDERING OF GRAPHITE GRAINS AND ITS APPLICATION TO ASTROPHYSICAL PROBLEMS

The size dependence of diamagnetic orientation is reported on micron-s ized graphite grains suspended in liquid ethanol at room temperature. The experiment was performed as a preliminary step to reproduce the ma gnetic alignment of astronomical dust particles in space. The mean gra in sizes of the two samples were 2.5 and 3.8 mu m in diameter with the field of full orientation H-S being 35.9 and 29.0 mT, respectively. T he present H-S obtained for graphite grains are the smallest values co mpared to any of the reported data on micron-sized particles. The diam agnetic orientation may be applicable to explain the grain alignment i n the cosmic dense cloud of a star formation region. (C) 1998 Elsevier Science B.V. All rights reserved.