Measurements Of Interaction Cross Sections For F19-27 Isotopes

Interaction cross sections (sigma(I)) and reaction cross sections(sigma(R)) are physical quantities which are strongly related to the nuclear size. In our previous study of sigma(I) for Ne isotopes, the deformation features of neutron-rich Ne isotopes in the so-called "island of inversion" region have been successfully observed, and also the formation of the deformed halo structure in Ne-31 has been indicated. In this study, sigma(I) for F19-27 up to the vicinity of the island of inversion have been measured at around 240A MeV using BigRIPS at RIBF, RIKEN. Our preliminary results are slightly larger than A(1/3) systematics and some of the data could be explained by nuclear deformation.