# Four-body continuum effects in 11Be+d scattering

## TL;DR

This paper introduces a four-body extension of the CDCC model to accurately describe reactions involving weakly bound nuclei like 11Be+d, emphasizing the importance of including continuum states of both nuclei for precise scattering analysis.

## Contribution

The paper develops a novel four-body reaction model extending CDCC to include continuum effects of both colliding nuclei, enabling improved analysis of weakly bound systems.

## Key findings

- Accurate elastic-scattering data description requires simultaneous inclusion of continuum states of 11Be and deuteron.
- The model predicts larger breakup cross sections for 11Be compared to the deuteron.
- The theory provides wave functions useful for analyzing reactions with radioactive beams.

## Abstract

We present a new reaction model, which permits the description of reactions where both colliding nuclei present a low threshold to breakup. The method corresponds to a four-body extension of the Continuum Discretized Coupled Channel (CDCC) model. We first discuss the theoretical formalism, and then apply the method to 11Be+d scattering at Ecm = 45.5 MeV. The 11Be nucleus and the deuteron are described by 10Be+n and p + n structures, respectively. The model involves very large bases, but we show that an accurate description of elastic-scattering data may be achieved only when continuum states of 11Be and of the deuteron are introduced simultaneously. We also discuss breakup calculations, and show that the cross section is larger for 11Be than for the deuteron. The present theory provides reliable wave functions that may be used in the analysis of (d,p) or (d,n) experiments involving radioactive beams.