Practical method for decomposing discretized breakup cross sections into components of each channel

Background: In the continuum-discretized coupled-channel method, a breakup cross section (BUX) is obtained as an admixture of several components different channels in multichannel scattering.Purpose: Our goal to propose approximate way decomposing discretized BUX into each channel. This approximation referred ``probability separation (P separation).''Method: As example, we consider $^{11}\mathrm{Be}$ scattering by using three-body model with core excitation ($^{10}\mathrm{Be}+n+T$, where $T$ target). The structural part constructed particle-rotor and reaction described distorted-wave Born approximation.Results: validity P tested comparing exact calculation. reproduces BUXs well regardless configurations and/or resonance positions $^{11}\mathrm{Be}$.Conclusion: method proposed here can be alternative approach for four- or five-body strict decomposition hard perform.