New Magic Number, $\mathit{N}=16\mathrm{}$, near the Neutron Drip Line

We have surveyed the neutron separation energies $\left(S_n\right)$ and the interaction cross sections $\left({\sigma }_I\right)$ for the neutron-rich $p-\mathrm{sd}$ and the $\mathrm{sd}$ shell region. Very recently, both measurements reached up to the neutron drip line, or close to the drip line, for nuclei of $Z\le 8$. A neutron-number dependence of $S_n$ shows clear breaks at $N=16\mathrm{}$ near the neutron drip line $(T_Z\ge 3)$, which shows the creation of a new magic number. A neutron-number dependence of ${\sigma }_I$ shows a large increase of ${\sigma }_I$ for $N=15\mathrm{}$, which supports the new magic number. The origin of the new magic number is also discussed.