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Nucleon transfer reaction in low-energy a + 6 He collisions and continuum structures of 10 Be. Unified studies from the nuclear structures and the nuclear reactions. M. Ito , K. Yabana Institute of Physics, University of Tsukuba K. Kato Div. of Phys., Grad. Sc. of Sci., Hokkaido Univ
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Nucleon transfer reaction in low-energy a+6He collisions and continuum structures of 10Be Unified studies from the nuclear structures and the nuclear reactions M. Ito, K. Yabana Institute of Physics, University of Tsukuba K. Kato Div. of Phys., Grad. Sc. of Sci., Hokkaido Univ K. Ikeda Institute of physical and chemical research, RIken
Ex. Introduction g.s. • Cluster structure (N=Z) 8Be = 2a, 12C = 3a, 20Ne = a+16O • Clusters + Valence neutrons Be = 2a+Xn : Molecular Orbital C = 3a+Xn : Linear chain, D3h Symmetry N. Itagaki et al. Ne = a+16O+Xn : l=3 deformation W. von. Oertzen
Dynamics in the Two cores + XN system ER, G Collisions s (E), ds/dW Decays Res. Breakup Excitations Nuclear Reactions G.S. Should be combine !! Nuclear Structures
Be isotopes( a + a + n + n +…. ) • Low-lying states : Molecular Orbital 10Be = (p-)2 12Be = (p-)2 (s+)2 p- s+ Clustering !! • Resonant states : 6He or 8He ?? • Be → He + He • M. Freer et al. • Saito et al. a+6He collisions R. Raabe et al. 10Be=a +6He 12Be=6He+6He
Our approach ( 10Be=a+a+n+n ) • Description of the internal and asymptotic states Generalized Two-center Cluster Model (GTCM) • Resonance parameters in compound system Absorbing-kernels in Generator Coordinate (AGC) ( Absorbing Boundary Condition ) • Reaction cross section Kohn-Hulthen-Kato’s method (KHK) ( Incident and exit channels ) A.O. M.O. ーi W(R)
OurModel ( 10Be = a + a + n+ n ) I x L = J L PJpMK OR I Mol. Orb. Weak coupling = + + PJpMK + ... + 0Pi (i=x,y,z)
Generalized Two-center Cluster Model ( I ) • Basis function FJpK(n,S) = PJpMK A { fL(a) fR(a) c(n)}S • f(a) : a particle, (0s)4 in H.O. • c(n) :Neutrons( Left or Right, 0px,0py,0pz ) S
Generalized Two-center Cluster Model ( II ) • Total wave function • YJp= SS SKnf(n,S,K) FJpK(n,S) • = SS GJp(S) • Eigenvalue Problem <FJpK(n,R) | H – E | YJp> = 0 • Adiabatic Energy Surfaces <FJpK(n,S) | H – E(S) | GJp(S)> = 0 ( H = S t i + S v ij )
Adiabatic energy surfaces (Volkov No2. + G3RS) • Red Dots [ a + 6He ( I ) ] LJ a + 6He(01+) • Blue Dots [5He(I1) + 5He (I2)]LJ
Results of GTCM + AGC for 10Be(0+) Energy spectra ( Jp = 0+ ) Adiabatic surfaces (Jp = 0+)
Results of GTCM + AGC + KHK for 10Be(0+) (a + 6He) + (5He + 5He) : 6He→01+,21+,02+,22+, 5He→3/2-,1/2- a+6He(01+) → a+6He(21+)
Crossing of adiabatic surfaces in 10Be Jp = 1- (Pseudo Crossing) Jp = 0+ (Gradual Coupling)
Coupled ch. In adiabatic basis for 10Be(0+) a+6He g.s. Elastic scattering Adiabatic process is dominant.
Coupled ch. In adiabatic basis for 10Be(1-) a+6He g.s. Elastic scattering Non-adiabatic transition strongly occurs.
Summary and Conclusion 1. Studies on Clustering and the valence nucleons It is very interesting and important to study the nuclear structures and their enhancements in reactions. 2. GTCM + AGC + KHK It is possible to study from the point of view of the nuclear reaction and structures. 3. Applications to 10Be ⇒ Systematic studies !! Excitation of 03+ and 04+ ⇔ Intrinsic structures 1- ⇒ Non-adiabatic process is dominant due to the appearance of a + 6He clusters.