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