Eikonal reaction theory for two-neutron removal reactions

The eikonal reaction theory (ERT) proposed lately is a method of calculating one-neutron removal reactions at intermediate incident energies in which Coulomb breakup is treated accurately with the continuum discretized coupled-channels method. ERT is extended to two-neutron removal reactions. ERT reproduces measured one- and two-neutron removal cross sections for ${}^6\mathrm{He}$ scattering on ${}^{12}\mathrm{C}$ and ${}^{208}\mathrm{Pb}$ targets at 240 MeV/nucleon and also on a ${}^{28}\mathrm{Si}$ target at 52 MeV/nucleon. For the heavier target in which Coulomb breakup is important, ERT yields much better agreement with the measured cross sections than the Glauber model.

Figure 1

Elastic breakup (${\sigma }_{\mathrm{br}}$), one-neutron stripping (${\sigma }_{1n\mathrm{str}}$), two-neutron stripping (${\sigma }_{2n\mathrm{str}}$), two-neutron removal (${\sigma }_{-2n}$), and total reaction cross sections (${\sigma }_{\mathrm{R}}$) for ${}^6\mathrm{He}$ scattering from ${}^{12}\mathrm{C}$ (upper panel) and ${}^{208}\mathrm{Pb}$ (lower panel) at 240 MeV/nucleon. The right vertical axis stands for ${\sigma }_{\mathrm{R}}$, whereas the left one does for ${\sigma }_{\mathrm{br}}$, ${\sigma }_{1n\mathrm{str}}$, ${\sigma }_{2n\mathrm{str}}$, and ${\sigma }_{-2n}$. The ERT and Glauber-model results are shown by the circles and triangles, respectively. Experimental data are taken from Ref. [25].

Figure 2

The same as Fig. 1 but for ${}^6\mathrm{He}$ scattering from a ${}^{28}\mathrm{Si}$ target at 52 MeV/nucleon. Experimental data are taken from Ref. [30].