Proton Elastic Scattering of(23,25)F

Proton elastic scatterings of neutron-rich nuclei 23F and 25F have been measured for the first time at 289 and 298 MeV/nucleon, respectively, using the MUST2 silicon strip detector array and RIBF facility at RIKEN. The differential cross section of 25F was found to be smaller than the calculation with the global potential by Koning and Deraloche. The small cross section of 25F can be well reproduced by an optical model calculation with a shallow and long-tail potential.