skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Porous fission fragment tracks in fluorapatite

Journal Article · · Physical Review. B, Condensed Matter and Materials Physics
;  [1];  [1];  [1];  [2];  [3]
  1. Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2104 (United States)
  2. Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1005 (United States)
  3. GSI Helmholtz Centre for Heavy Ion Research, Planckstr. 1, 64291 Darmstadt (Germany)

Fission tracks caused by the spontaneous fission of {sup 238}U in minerals, as revealed by chemical etching, are extensively used to determine the age and thermal history of Earth's crust. Details of the structure and annealing of tracks at the atomic scale have remained elusive, as the original track is destroyed during chemical etching. By combining transmission electron microscopy with in situ heating, we demonstrate that fission tracks in fluorapatite are actually porous tubes, instead of having an amorphous core, as generally assumed. Direct observation shows thermally induced track fragmentation in fluoapatite, in clear contrast to the amorphous tracks in zircon, which gradually ''fade'' without fragmentation. Rayleigh instability and the thermal emission of vacancies control the annealing of porous fission tracks in fluorapatite.

OSTI ID:
21421452
Journal Information:
Physical Review. B, Condensed Matter and Materials Physics, Vol. 82, Issue 14; Other Information: DOI: 10.1103/PhysRevB.82.144109; (c) 2010 The American Physical Society; ISSN 1098-0121
Country of Publication:
United States
Language:
English