Four-body CDCC in coulomb breakup reactions

The pseudostate method has been introduced to Continuum-Discretized Coupled-Channels (CDCC) method to apply CDCC to four-body system reactions. Effectiveness of this method has been shown for nuclear force breakup reactions already but not yet for Coulomb breakup reactions. In this report, effectiveness of this method for Coulomb breakup reaction is examined. As the first step, the three-body Coulomb breakup reaction of 8B + 58Ni with projectile energy 25.8 MeV is taken up. Here 8B is regarded as the two-body system of p + 7Be. For this reaction, correct results are obtained by the conventional average method. The new CDCC calculation on the completely same model space is executed with pseudostate method. S-matrices and total reaction cross sections of the both calculations agree satisfactorily, which indicates the validity of the pseudostate method. Then the new method is applied to the elastic scattering 6He + 209Bi with projectile energy of 19 MeV. The elastic scattering cross section is calculated regarding 6He as 4He + n + n for four-body case and compared with the three-body calculation assuming 6He=4He+2n for convenience. Results show considerable difference between them. It is concluded that 6He should be regarded as three-body. (S. Funahashi)