Positron annihilation lifetime spectroscopy study of vacancy cluster evolution in swift heavy ion irradiated HOPG

نویسندگان

  • M. Krause
  • W. Egger
  • C. Hugenschmidt
  • L. Ravelli
  • C. Trautmann
چکیده

Isotropic carbon is the material of choice for the rareisotope production target and beam catchers of the future Super-FRS. During operation both components are exposed to high-intensity ion beams and may suffer from radiation damage. To better understand damage formation processes in graphite, irradiation experiments were performed at the X0 beamline using 11.1 MeV/u Au-ions and different fluences. As material we selected highly oriented pyrolytic graphite (HOPG), because in contrast to isotropic graphite, it has a well defined structure and as such serves as a model material. The irradiated samples were studied by positron annihilation lifetime spectroscopy (PALS) performed at the pulsed low-energy positron system (PLEPS) at the Munich research reactor FRM II [1].

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تاریخ انتشار 2011