Ozawa A, Kobayashi T, Suzuki T, Yoshida K, Tanihata I
The Institute of Physical and Chemical Research (RIKEN), Hirosawa 2-1, Wako-shi, Saitama 351-0198, Japan.
Phys Rev Lett. 2000 Jun 12;84(24):5493-5. doi: 10.1103/PhysRevLett.84.5493.
We have surveyed the neutron separation energies (S(n)) and the interaction cross sections (sigma(I)) for the neutron-rich p-sd and the sd shell region. Very recently, both measurements reached up to the neutron drip line, or close to the drip line, for nuclei of Z</=8. A neutron-number dependence of S(n) shows clear breaks at N = 16 near the neutron drip line (T(Z)>/=3), which shows the creation of a new magic number. A neutron-number dependence of sigma(I) shows a large increase of sigma(I) for N = 15, which supports the new magic number. The origin of the new magic number is also discussed.
我们已经对富中子的p-sd和sd壳层区域的中子分离能(S(n))和相互作用截面(σ(I))进行了测量。最近,对于Z≤8的原子核,这两项测量都达到了中子滴线,或者接近中子滴线。S(n)对中子数的依赖关系在靠近中子滴线(T(Z)≥3)的N = 16处出现明显的间断,这表明出现了一个新的幻数。σ(I)对中子数的依赖关系表明,对于N = 15,σ(I)大幅增加,这支持了这个新的幻数。同时也讨论了新幻数的起源。