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In the reactions Be 9 (α, 2α)He 5 and C 12 (α, 2α)Be 8 at 28 MeV, the single and summed energy spectra of emitted alpha-particles have been measured at several pairs of angle in order to investigate the quasi-free collision between incident alpha-particles and alpha-clusters in Be 9 and C 12 . The summed energy spectrum of the alpha-particles from the reaction Be 9 (α, 2α)He 5 shows a peak corresponding to the ground state of He 5 at the angles at which the emitted particles come from the collision between incident alpha-particles and nearly zero-momentum alpha-clusters in Be 9 . The momentum spread of the alpha-cluster in Be 9 coupled with He 5 (ground state) is estimated to be 0.3 fm -1 from the angular correlation of the peak in the summed energy spectrum, and the probability of finding an alpha-cluster in this state is 0.12, if a plane wave impulse approximation is assumed. In the reaction C 12 (α, 2α)Be 8 g'nd , the yield has a minimum at the angles expected from the quasi-free collision between incident alpha-particles and nearly zero-momentum alpha-clusters in C 12 . The state in which an alpha-cluster is bound to Be 8 (ground state) in C 12 seems to be very different from that for Be 9 .
References
- 1 T.Yanabu: J. Phys. Soc. Japan 16 (1961) 2118; S.Yamashita: J. Phys. Soc. Japan 16 (1961) 2378; T.Yanabu, S.Yamashita, T.Nakamura, K.Takamatsu, A.Masaike, S.Kakigi, D. C.Nguyen, and K.Takimoto: J. Phys. Soc. Japan 16 (1961) 2594; T.Nakamura, K.Takamatsu, A.Masaike, S.Kakigi, D. C.Nguyen, S.Yamashita and T.Yanabu: J. Phys. Soc. Japan 17 (1962) 19; K.Takamatsu: J. Phys. Soc. Japan 17 (1962) 892; T.Yanabu, S.Yamashita, T.Nakamura, K.Takamatsu, A.Masaike, S.Kakigi, D. C.Nguyen and K.Takimoto: J. Phys. Soc. Japan 17 (1962) 914; T.Yanabu, S.Yamashita, T.Nakamura, K.Takamatsu, A.Masaike, S.Kakigi, D. C.Nguyen and K.Takimoto: J. Phys. Soc. Japan 18 (1963) 742. Link, Google Scholar
- 2 T.Yanabu, S.Yamashita, S.Kakigi, D. C.Nguyen, K.Takimoto, Y.Yamada and K.Ogino: J. Phys. Soc. Japan 19 (1964) 1818. Link, Google Scholar
- 3 C.Ruhla, M.Riou, M.Gusakow, J. C.Jamart, M.Liu and L.Valentin: Phys. Letters 6 (1963) 282. Crossref, Google Scholar
- 4 A.Sammon and P.Cüer: J. Phys. Radium 19 (1958) 13; A. N.James and H. G.Pugh: Nuclear Phys. 42 (1963) 441; T.Yuasa: Phys. Letters 8 (1964) 318. Crossref, Google Scholar
- 5 T. J.Gooding and G.Igo: Phys. Rev. Letters 7 (1961) 29; G.Igo, L. F.Hansen and T. J.Gooding: Phys. Rev. 131 (1963) 337. Crossref, Google Scholar
- 6 J.Hiura: private communication. Google Scholar
- 7 Y.Sakamoto: Nuclear Phys. 66 (1965) 531. Crossref, Google Scholar