Elastic Scattering of 17Ne and 15O from 28Si

Elastic scattering angular distributions of 17Ne + 28Si at Elab=22.4 MeV/u and 15O + 28Si at Elab=18.2 MeV/u, well above the Coulomb barrier (Ecm/VB=9.7 and 8.2, respectively), have been measured at the HIRFL–RIBLL facility in Lanzhou. Time of flight–ΔE (TOF–ΔE) beam identification, PPAC-based trajectory tracking, and a target–detector integrated DSSD telescope were employed for event-by-event reconstruction of scattering angles and particle identification. Detection efficiencies and solid angles were evaluated and corrected by means of Geant4 simulations. Theoretically, the real parts of the optical potentials were calculated within a double-folding model using the density-dependent BDM3Y1–Paris effective interaction, while the imaginary parts were taken as Woods–Saxon forms and adjusted by χ2 fits to the data using the SFRESCO code. 17Ne has a larger matter distribution than 15O. However, once mass scaling is removed, the real potential remains essentially unchanged, indicating the structural effects are not encoded in the real part. At the same time, a substantially deeper imaginary potential is required for the 17Ne + 28Si system, pointing to stronger absorption and coupling effects. A further analysis in terms of the reduced distance of closest approach shows that both the strong-absorption distance dS and the effective coupling range Δd are larger for 17Ne than for 15O, whereas the Coulomb barrier height VB follows the known systematics and is insensitive to structural differences. These findings provide reaction-based evidence that the more diffuse and weakly bound structure of 17Ne has a pronounced impact on the scattering dynamics on a light- to medium-mass target.