Quasi-Free Scattering Studies in and Around the Ca Mass Region

Quasi-free scattering studies in the Ca mass region have been conducted by the R3B collaboration at GSI in inverse kinematics, with the goal of studying the nuclear structure of both stable and exotic nuclei. This work focuses on studying the
single-particle strength in this region, which is achieved through cross-section measurements. Preliminary quasi-free scattering cross sections have been calculated for both AX(p,2p)A−1Y and AX(p,pn)A−1X reaction channels for the Ca isotopic chain,
with the use of CH2 and C targets. Theoretical (p,2p) cross sections for Ca isotopes were calculated using single-particle cross sections deduced from quasi-free reaction
theory based on the Eikonal model. Experimental spectroscopic factors have been calculated for quasi-free scattering (p,2p) reactions for the Ca isotopic chain assuming the orbit occupation expected by the independent particle model. The values are quenched and are consistent with (e,e’p) data for stable nuclei, showing a weak correlation with nuclear asymmetry, confirming earlier R3B measurements using lighter
nuclei. Additionally, research and development for a new target-recoil tracker based on monolithic active pixel sensors for the R3B experiment are reported here for the first time. Together with the conceptual design for a full barrel configuration which
is to be used at the planned FAIR facility.