The differential cross sections of the B11(He3,d)C12 reaction leading to formation of the 0+ ground state and the 15.11-MeV 1 +, 16.57-MeV 2−, and 17.23-MeV 1− excited states of C12 are measured at Elab=25 MeV. The analysis of the data is carried out within the coupled-reaction-channels method for the direct proton transfer to the bound and unbound states. The rms radii of the last proton in all states studied are determined. A comparison of the rms radii of the B12, C12, and N12 nuclei in the isobaric analog states (IASs) with isospin T=1 determined by different methods allows us to arrive at a conclusion that these nuclei in the 1− excited states at Ex=2.62, 17.23, and 1.80 MeV, respectively, possess one-nucleon (neutron or proton) halo structure. The enlarged radii and a large probability of the last neutron to be outside of the range of the interaction potential are also found for the 2− states of B12, C12, and N12 at Ex=1.67, 16.57, and 1.19 MeV, respectively. These IASs also can be regarded as candidates for states with one-nucleon (neutron or proton) halo.

中文翻译：

---

A=12 原子核等压模拟态中可能的中子和质子晕结构

B11(He3,d)C12 反应导致形成 0+ 基态和 C12 的 15.11-MeV 1 +、16.57-MeV 2- 和 17.23-MeV 1- 激发态的微分截面在Elab=25 MeV。数据分析是在耦合反应通道方法中进行的，用于将质子直接转移到结合和未结合状态。确定了所有研究状态中最后一个质子的均方根半径。比较 B12、C12 和 N12 原子核在等压类似态 (IAS) 与通过不同方法确定的同位旋 T=1 的 rms 半径，我们可以得出结论，即这些原子核在 Ex 的 1− 激发态=2.62、17.23 和 1.80 MeV，分别具有单核子（中子或质子）晕结构。在 Ex=1.67、16.57 和 1.19 MeV 处，B12、C12 和 N12 的 2-态也发现了扩大的半径和最后一个中子在相互作用势范围之外的大概率。这些 IAS 也可以被视为具有单核子（中子或质子）晕的状态的候选者。