Slow positron production using the RIKEN AVF cyclotron
1995; Elsevier BV; Volume: 85; Linguagem: Inglês
10.1016/0169-4332(94)00327-0
ISSN1873-5584
AutoresYoshiko Itoh, K.H. Lee, Terunobu Nakajyo, Akira Gotō, Noriyoshi Nakanishi, M. Kase, Ikuzo Kanazawa, Yosiaki Yamamoto, Nagayasu Oshima, Yasuo Ito,
Tópico(s)Atomic and Molecular Physics
ResumoUsing the RIKEN AVF cyclotron, various targets were irradiated with proton or deuteron beams to produce β+-decay radioisotopes. Slow positrons are extracted backward at an angle of 30° to the incident ion beam using a well annealed W film, with a thickness of 10 μm, as a moderator. This geometry was chosen to allow for both the use of various kinds of target materials and the in-beam slow positron extraction during ion beam irradiation. In preliminary experiments, a slow e+ intensity of ∼5.6 × 104 e+/s was obtained from BN by irradiating protons with an energy of 14 MeV and a current of 4 μA. From an Al target irradiated with a proton beam with an energy of 10 MeV and a current 3.6 μA, a slow e+ intensity of ∼5.5 × 102 e+/s was also obtained. By irradiating a deuteron beam with 8 MeV energy and 1.3 μA current, slow e+ intensities of ∼4.2 × 103 e+/s and ∼3.4 × 103 e+/s were obtained from carbon and Si3N4 respectively. Using a pulsed ion beam, background noise was eliminated almost completely in three-coincidence measurement.
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