Evolution of the IVGDR and its fine structure from doubly-magic ⁴⁰ Ca to neutron-rich ⁴⁸ Ca probed using (p, p ⁰ ) scattering

Experiments investigating the fine structure of the Isovector Giant Dipole Resonances (IVGDR) have been carried out on target nuclei ^40,42,44,48 Ca with 200 MeV proton inelastic scattering reactions using the high-energy resolution capability and the zero-degree set-up at the K600 magnetic spectrometer of the iThemba LABS, Cape Town, South Africa. Quasi-free scattering background contributions in the experimental data have been removed by applying a novel method of Discrete Wavelet Transform (DWT) analysis. Energy scales extracted are compared with the state-of-the-art theoretical calculations within the framework of the Quasiparticle-RPA and Relativistic Quasiparticle Time Blocking Approximation (RQTBA). For ^40,48 Ca, these calculations consider all major processes (Landau damping, escape width, spreading width) contributing to the damping of the IVGDR.